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Butch Lambert
01-19-2008, 11:13 AM
Have you seen the preview of the Grizzly chambering video on 6mmBR.com? Check it out and explain to me how he is indicating the bore.
Butch

mike in co
01-19-2008, 12:16 PM
well butch.....

hmmmmm
he is using the spyder to move the opposite end of the bbl.....(everything pivoting on the chuck jaws)

i think his method is to align a section of the bore to be straight at the reamer side.......my guess is that he assumes that if this section of bore is in line with the reamer....the chamber is inline with the bore......

just one more method......if his guns shoot i guess it works...

mike in co...

wnroscoe
01-19-2008, 12:35 PM
I spoke with a very well known reamer manufacturer about the rod Mr. Gritters is using. He said they use to make them but, due to their length run out was a problem. As far as the rod goes for indicating, the double lock up method, bushing & taper, was still the best method as far as he was concerned. Mr. Gritters inidcating rod appeared to be about 18" or so and he was using the tail stock to hold/insert it in the bore 2" or more at a time. I guess you cant argue with his success, just one more way to do it.

JJ-IA
01-19-2008, 02:43 PM
Here’s the YouTube video.
http://www.youtube.com/watch?v=aII2tbavKnM

I don’t have the DVD, what cartridge is he chambering and how much muzzle runout there was after the setup?


Check it out and explain to me how he is indicating the bore.
Butch
It looks like the long stem indicator, wobbly muzzle, indicate the throat and slightly beyond as a cylinder method discussed several times in this forum. But he’s using a piloted rod on top of the lands (and indicating off the rod at a mid point) instead of pre boring and using a long indicator stem reading the grooves.
It looks like a good setup of you’re going to ream the entire chamber and not going to pre-bore.


.......my guess is that he assumes that if this section of bore is in line with the reamer....the chamber is inline with the bore......

I don’t believe he’s assuming anything Mike, if the setup is for a 6ppc he’s indicating ½” past the chamber.


I spoke with a very well known reamer manufacturer about the rod Mr. Gritters is using. He said they use to make them but, due to their length run out was a problem. As far as the rod goes for indicating, the double lock up method, bushing & taper, was still the best method as far as he was concerned. Mr. Gritters inidcating rod appeared to be about 18" or so and he was using the tail stock to hold/insert it in the bore 2" or more at a time. I guess you cant argue with his success, just one more way to do it.
Rod runout wouldn't be a factor because the rod isn’t turning, only the pilot. Unless the rod is bent so much that it contacts the bore instead of the bushing, or cocks the bushing itself causing rod flex when the barrel is rotated.

Interesting video none the less.

Shiraz Balolia
01-19-2008, 03:23 PM
What you see on 6mmBR is a miniscule part of the chambering video, a teaser if you will. To understand exactly what he is doing and why he is doing it you should watch the whole 90 minute video.
Gordy builds extremely accurate benchrest rifles and has built world record holding guns.

dennisinaz
01-19-2008, 04:40 PM
I have watched to whole DVD and what he is saying makes sense. He just calls it a range rod and doesn't talk too much about it. I suppose he isn't giving everything away.

He basically lines up the first2 2"-3" of the bore and doesn't worry about the muzzle end. In fact, on the barrel he chambered, you could see the muzzle run out in the spider- maybe .005-.006 or so. This is just to make a point of the bore not being PERFECTLY straight.

Dusty Stevens
01-19-2008, 05:27 PM
I'd like to see that video

Chisolm
01-19-2008, 05:29 PM
I'd like to see that video

http://www.grizzly.com/products/DVD-Chambering-A-Championship-Match-Barrel/H8396
or if you mean the video clip look at post#4.
James

Chisolm
01-19-2008, 05:52 PM
What Gordy is using is a 12” piece of drill rod machined to hold a reamer bushing with minimal clearance. As someone else stated the rod is held in the tailstock so rod run out isn’t an issue.
I chambered my last barrel using Gordy’s method and setup was surprisingly simple and quick.
But whenever you chamber a barrel you have to make a compromise somewhere along the way because of the curved bore.
You may remember an earlier thread discussing bore curve where I tried to point out that the bore isn’t a perfect arc but has a curve to it, more like a helix. That is the one thing that I don’t know how to properly address with any setup. Anyway after chambering and threading the barrel and indexing it I flipped it around and indicated the muzzle to cut the crown using the same method to indicate as the chamber and found as I expected would be the case the muzzle actually pointed a little off to the right instead of straight up because the helical curve in the bore. But regardless, with what little testing I have done with the barrel I believe it will shoot well enough(been too damn cold to do much testing). I also know that Gordy makes some extremely accurate rifles so his method must be sound. Gordy’s method does do an excellent job of making sure that the first rifling that the bullet hits is dead true with the bullets travel and has the cartridge and bullet dead centered and in line with the beginning of the bore.
As has been said many times on this forum there are many ways to chamber an accurate rifle you just need to find what method you are most comfortable with.
The next barrel I do will be chambered with Gordy’s method also.
James

mike in co
01-19-2008, 06:35 PM
ok...what some others do( from what i have read) is to cut a chamber inline to a point where the throat is expected to be. what i believe gordy is trying to do is make a chamber that is "pointing" along the bore meeting at the throat. this assumes the the curve/spiral is continuous and smooth. that was the assumption i was talking about. his chamber is not necessarily parrallel to the bbl...as others have pointed out the was visible run out on the muzzle....and as was just said when the muzzle is crowned the same way, the face is not perpenticular to the od....but is to the last of the bore.

just one more way ro skin a cat....

mike in co

pduryee
01-19-2008, 07:54 PM
Guess I missed something in the video and need to watch it a few more times. I was under the impression that he got the chamber end close first by adjusting the spider then switched to the four jaw to dial it in. Then he adjusted the muzzle true by adjusting the spider and the chamber end by the four jaw....switching back and forth until both were running true. Speaking as a novice at this stuff and teaching myself machine work I can say that I learned a lot from the video and am very satisfied with the 4003 lathe.

JerrySharrett
01-19-2008, 08:00 PM
I'll admit the Gritters method is ingenious but when you get done chambering, turning the tenon and shoulder that butts up against your action, where is the muzzle pointing?? Is it pointing up or down or left or right???

JJ-IA
01-19-2008, 08:18 PM
I'll admit the Gritters method is ingenious but when you get done chambering, turning the tenon and shoulder that butts up against your action, where is the muzzle pointing?? Is it pointing up or down or left or right???

IIRC, a post in a different thread said he indicates the barrel so the muzzle runout is on the vertical plane, high side up.

alinwa
01-19-2008, 08:33 PM
Jerry, you obviously haven't seen the vid. Gordy clocks his barrels so that the bend is up, right wrong or indifferent this is where he SETS it, no guesswork.


Regarding all of the other posts picking on Gordie's methods.........none of you really seem to get it, even the "very well known reamer mfgr" is all wet on this one.


If ANY of you can actually EXPLAIN a better way, not just "9 ways to flay a cat" but explain your reasoning, then feel free but this Gordy Bashing is just stupid! :mad:

He did a great job on the video and showed me several K.I.S.S. simple improvements over my several ways..........the use of the range rod is simply inspired.


al

Chisolm
01-19-2008, 09:15 PM
Jerry
JJ is correct.
Mark the location that the muzzle is pointing up then fit the action so that it will be pointing up when assembled then chamber the barrel.
I don't want to take anything away from Gordy but after I had chambered a total of 4 barrels I pondered on how to do a better job of indicating a barrel (not that I had problems I just wasn't comfortable with it) and came up with the same idea that Gordy uses. I doubt that I would have ever tried it though, had I not known someone else was doing it this way with success. So there have got to be others doing it this way too but you just don't hear about it, or anyway I haven't(didn't know Gordy was doing it this way until I got the video).
The issues that I had with trying it were:
1)How accurate can it be indicated using secondary measurements off the indicator rod.
2)Dealing with the helical curve with the bore, which is an issue no matter how you indicate the barrel.


Gordy doesn't only set the barrel up using the indicator rod, he also uses a Mitutoyo indicator with a long stylus that he reaches into the bore to recheck the runout.
With the Mitutoyo and long stylus, after rough drilling he is able to reach way in and check the runout of the bore where the throat will be before boreing and reaming the chamber.
I do not have a test indicator with long stylus like Gordy yet, maybe in the future:).
I hope what I posted makes sense.
James

dennisinaz
01-19-2008, 09:46 PM
One thing that is evident throughout the DVD is that he is fanatically meticulous at each stage that everything is running right- he leaves nothing to chance. If it out a little, he fixes it before going on. He even bore scopes the progress as he engages the rifling with the reamer...

All in all, a very thoughful process.

Spott3r
01-19-2008, 10:17 PM
..in the Video/DVD is the G0509G Professional Gunsmith Lathe.

http://www.grizzlyimports.com/products/16-x-40-3-Phase-Gunsmith-Metal-Lathe/G0509G

Just to be clear..:)

Dealing with the helical curve... it really doesn't matter what the bore does with this method. The method indicates possibly the best procedure to align the action and esp. the chamber with the intial bore concentricity. So when the Bullet leaves the chamber it is aligned directly/exactly with the bore direction.

OK...I'll stop there because I don't want to....bore you!!! :eek::D:D

It is a 7mm barrel blank.

Really though, get the Video it is well worth it.

JerrySharrett
01-20-2008, 06:03 AM
Jerry
JJ is correct.
Mark the location that the muzzle is pointing up then fit the action so that it will be pointing up when assembled then chamber the barrel.

With the Mitutoyo and long stylus, after rough drilling he is able to reach way in and check the runout of the bore where the throat will be before boreing and reaming the chamber.
I do not have a test indicator with long stylus like Gordy yet, maybe in the future:).
I hope what I posted makes sense.
James
I have been threading round stuff on a lathe since 1955 with conventional half-nut and digital CNC lathes. If one of you can explain how you are going to "clock" a spot on a barrel so it finishes at the same place every time, in a glued in action that belongs to someone miles away, I'll gladly listen.

No, I don't need to see the video, just tell me via the written word.

Chisolm, don't waste your funds on the Mitutoyo. It's not a bad indicator but it sure is not the best. As Bruce Thom says, "cry once".

pduryee
01-20-2008, 07:17 AM
I have been threading round stuff on a lathe since 1955 with conventional half-nut and digital CNC lathes. If one of you can explain how you are going to "clock" a spot on a barrel so it finishes at the same place every time, in a glued in action that belongs to someone miles away, I'll gladly listen.

No, I don't need to see the video, just tell me via the written word.

Chisolm, don't waste your funds on the Mitutoyo. It's not a bad indicator but it sure is not the best. As Bruce Thom says, "cry once".



If you had the entire gun at some point and threaded a barrel using the method described. Could you then machine a reference gage that would stay in your shop along with the other gun specs? Seems like if you matched a new barrel to the clock position on the gage it should fit the action also.
Just a thought.

JerrySharrett
01-20-2008, 08:05 AM
If you had the entire gun at some point and threaded a barrel using the method described. Could you then machine a reference gage that would stay in your shop along with the other gun specs? Seems like if you matched a new barrel to the clock position on the gage it should fit the action also.
Just a thought.

Yes, IF. But your proposed IF doesn't come about very much except in building and barreling a gun the first time.

Much of this discussion is making a complicated solution to a non existent problem. A crooked barrel bore is normally not radial or circular. It is normally a compound curve. The important consideration is that the bullet centerline axis point straight into the bore at the freebore/leade area. It is also important that the exit point of that bullet be in linear alignment with the action/stock assembly.

If the entry point of the bullets cylindrical portion in the chamber neck is concentric with the bore at that point all is well and the bullet can get underway without problems of jacket distortion or in-bore skewing.

If the bullets exit point from the bore is not in perfect alignment in the horizontial (left-right) plane with the stock/action the gun will not track correctly.

I'm in no way trying to criticize Mr. Gritters quality of work or his results. I'm sure has a satisfied customer base. It's just with my background of machining and engineering I find it disturbing if the bore exit point doesn't point in the same direction as the bullets entry point.

Spott3r
01-20-2008, 10:33 AM
Jerry,

Simply, Gordy does account for the Exit Bore position.

How? Someone more knowledgeable than me will need to answer that. I'm going to watch the Video again...and again..and again...lol

-John

:)

Chisolm
01-20-2008, 10:41 AM
Jerry
I only chamber my own barrels so I always have the action on hand.
When you chamber a barrel without the action how do you determine where to stamp/engrave the cartridge information on the barrel? If you can get that in the exact clocked position you want it on the finished rifle I would think you could use the same technique to index the muzzle up. As I said I don't know just giving you ideas.
The reason for looking at the mitutoyo indicator is the small round body that can be inserted into the rough drilled chamber so as to get a direct reading into the bore. That is the only indicator that I have seen that will do that. Are there better quality ones that will accomplish that too?
James

jackie schmidt
01-20-2008, 04:35 PM
I finally got that download to work on my computer, and now see what Gordy is doing.
He is simply using the range rod as a substitute for a stylus on the indicator. The rod flexes. (the pivot is in the tailstock end), as the bore runnout is transfered through the bushing to the rod. The indicator stylus picks up the reading.
Several Gunsmiths I know use the same method of chambering. In other words, they are only interested in the first couple of inches of barrel that the reamer will actually be influenced by. If you get these first couple of inches dead true, you don't worry about everything else. The muzzle will, however, always exibit quite a bit of runnout, depending on how straight the bore is with its self.
I have never liked this method. The main reason is it is very difficult to set a barrel back up, which I do on a regular basis for set-backs. Second, some barrels have quite a bit of runnout,(as Jerry has noted, this can be in the form of several different curves), and I just do not like that much muzzle runnout.
I still favor the two point method, where you establish two dead true points, (that being the muzzle and the throat area), bore everything else on the chamber end in alignment with that, and then let the reamer follow the bored hole, assisted by the pilot. .
Keep in mind, if something is not straight, it is impossible to indicte more than two points dead true. (Unless you bend the piece). What you have to do is decide what two points you want, and work from there.
The basic difference in what Gordy does and what I do is what two points we decide to indicate dead true.
As I have said before, what really counts are the results. I would personally not use the methods described in this video, but if they work for Gordy, that is what counts..........jackie

crb
01-20-2008, 04:49 PM
I have a question for you guys that indicate the muzzle. Do you try to find out which way the bore is actually pointing when the muzzle is running true? Do you run some sort of indicator several inches into the bore at the muzzle to see which way it is pointing ?

Thanks

Chisolm
01-20-2008, 05:20 PM
Jerry
I just re-read through this thread and saw that you probably haven’t watched the video clip on 6BR.com so a lot of what I posted probably doesn’t make sense.
Your description of the bore being a compound curve is probably a better description than what I have been calling a helix. I guess I couldn’t come up with a better description and was thinking what it would be if it continued on past the end of the barrel. From now on I’ll call it a compound curve, maybe people will understand what I’m talking about then.:D
I’ll try to clarify some stuff.
The barrel is set up through the headstock with a spider on the outboard end.
The first 2to3” are then indicated in on the chamber end using the rod I described in an earlier post that is in the drill chuck in the tailstock. The rod is moved back and forth to adjust the chuck and spider until there is no runout in the 1st 2 to 3” of the bore.
After the barrel is indicated in, then put an indicator on the muzzle end and turn the lathe and find where the highest point of runout is and mark that as the point that will be up when installed on the action.
This method doesn’t address the radial curve of the bore at the muzzle, but then neither does centering both the muzzle and chamber end like most gunsmiths do.
James

JerrySharrett
01-20-2008, 08:01 PM
Jerry
I only chamber my own barrels so I always have the action on hand.
When you chamber a barrel without the action how do you determine where to stamp/engrave the cartridge information on the barrel? If you can get that in the exact clocked position you want it on the finished rifle I would think you could use the same technique to index the muzzle up. As I said I don't know just giving you ideas.
The reason for looking at the mitutoyo indicator is the small round body that can be inserted into the rough drilled chamber so as to get a direct reading into the bore. That is the only indicator that I have seen that will do that. Are there better quality ones that will accomplish that too?
James
James, many of the top custom actions have the same index point. I can change a barrel from one Panda to another and the print comes out at the same location...that is only if the Action or bolt face haven't been dickied with. But then again, many of other top custom actions do not have the threads starting in the same location.

Indicators? Read this web site well if you are interested in dial indicator precision and design.
http://longislandindicator.com/p116.html From this page go back to the first page and look at the others. They are listed alphabetically.

And yes I saw the video on 6mmbr.com and youtube. That is when I really started questioning that method of barrel alignment.

ArtinNC
01-20-2008, 10:15 PM
jackie,

You stated that "and I just do not like that much muzzle runnout." . Gordy indicated the muzzle end of the barrel the same way he did the chamber end so when he crowned the barrel it was square to the bore, isn't that what you want? The way I take it in the video, if you do the indicator on both ends , the bore could be at a slant to the crown. And I take it that it doesn't make any difference what the bore does between the throat and the muzzle .
Hope this makes since, I'm just trying to under stand the video and the posts here.
Thanks ,Art

PS: I just received the video Saturday.

alinwa
01-21-2008, 12:01 AM
Jerry,


Please elaborate on this statement .......... "If the bullets exit point from the bore is not in perfect alignment in the horizontial (left-right) plane with the stock/action the gun will not track correctly."


Explain how you measure and correct for this?


al

Spott3r
01-21-2008, 12:55 AM
Can someone make a 90min video of the two-point method.

Until then...;)

JerrySharrett
01-21-2008, 06:00 AM
Jerry,


Please elaborate on this statement .......... "If the bullets exit point from the bore is not in perfect alignment in the horizontal (left-right) plane with the stock/action the gun will not track correctly."


Explain how you measure and correct for this?


al
Al, if the barrel is pointing to the side, left or right, the gun will jump to the side, just like a bad bedding job where the action is crooked in the stock.

Action, equal and opposite reaction, comprande'?

How do you correct for this? chamber and fit the barrel so that the exit point is in alignment with the action/stock assembly.

There is apparently a method used called "clocking" the muzzle. A lot of extra work for a problem that was needless. One poster on this form some weeks ago points the muzzle up do gravity will pull it down??? Thass what he said anyhoo.

Gordy Gritters
01-21-2008, 10:22 AM
I certainly do not feel like anyone has been bashing me - it's just nice to see some discussion and other opinions on this topic. There definitely are other ways to set up and chamber barrels that work very well, but the way I'm currently doing it has produced consistently better results for me than ways I've done in the past.

I am a full-time gunsmith and have been doing this for about 21 years now. I do from 50 to 75 barrels a year and I've always continually experimented to try to find better ways of doing things. I did it between centers for awhile, and then for a long time I did it by indicating at the throat and the muzzle like a lot of guys do now and got along just fine, but when I changed my methods and started to set the bore up so the chamber perfectly aligns to the first few inches of bore AHEAD OF THE CHAMBER like I do now, my percentage of "so-so" barrels noticeably went down and the number of "hummer" barrels went up.

I first noticed this when I saw in my bore scope that the throat wasn't always as perfectly true as it should be. Then when I measured with an indicator, the chamber and the throat would be perfectly true, but even as close as 1/2" ahead of the throat I was surprised just how much runout there would be on some of these barrels (the more curvature in the barrel, the worse this is) - this really bothered me since my customers were paying good money and I felt I wasn't giving them their money's worth. Doing it the way I do now, I can measure the back of the chamber, the front of the chamber, the throat and 2" or more up the bore ahead of the throat and everything is still running straight and true - every single time - which is exactly how I want it.

You guys are right about the range rod. It doesn't turn so it doesn't matter if it's true or not. If the bore is running out, it will flex the rod along with it and this is easy to measure and use to get the bore running true. After I get it running true with the range rod, I always double-check the bore (and fine tune it if needed) with the dial indicator since it will give a more accurate reading than the range rod can (range rod bushing has clearance in the bore, it runs on top of the lands which aren't always true, and the bushing itself isn't always perfectly true).

I try to control everything as much as I possibly can, so I then started to index the "high side" of the muzzle end of the barrel so it pointed up. When setting a barrel up like this, even though the curvature in the bore isn't always "straight up" but sometimes will also curve a little right or left of center also (compound curve), the bore will still be generally be pointing up or close to it. This makes it better for long range shooting. I used to worry about the muzzle runout using this method, but after seeing the results for me, I sure don't worry about it any more. But the bigger benefit in my mind is no matter what the bore is doing at the muzzle end, I don't want the WEIGHT of the barrel at the muzzle hanging to the side at 3 o'clock or 9 o'clock - I feel this could be cause for more problems from harmonics and barrel whip.

There are so many details that are not on the DVD, but we hopefully cover the basics well enough for just about anyone who watches the DVD to do it that way if they want to and end up with extremely good results- that was one of the main purposes of this DVD! Hope this addresses some of what you guys are wondering about.

Gordy Gritters

Russ Hardy
01-21-2008, 11:40 AM
I have experienced the same thing as Mr. Gritters in my short experience of barrel chambering. I use an indicator to reference off the grooves and not the lands, but that limits how far I can indicate in past the throat. I have seen the same runout in front of the throat that Mr. Gritters describes when the muzzle end is running true. I was always a little uncomfortable with the runout at the muzzle end when I had my indicator readings true for the throat end of the barel. I have to be extremely "fussy" about getting very small runout readings ahead of the throat, since I can't reach in there very far (only about 2.5").

Russ Hardy
01-21-2008, 11:58 AM
Jerry,

I have had a lot of bag guns and my experience has been that the misalignment of the actons in the stock has been many magnitudes greater than any misalignment that could come from muzzle runout. Untill a greater number of gunsmiths go to some type of fixture to deal with alignment when bedding, I'm afraid that will be of much more concern with respect to tracking. I can set up my rests and put different rifles with the same stock in the bags and some will point up to 3 feet off of some others.

Just my experience.
Russ

jackie schmidt
01-21-2008, 12:53 PM
All I have watched of this video is what is posted on 6mmbr.com. From what I see, after Gordy indicates his barrel in forhis chambering and subsequent machining operations on the chamber end,, he pays no attention to what the muzzle is doing as far as runnout is concerned.
Where you can run into a (minor) problem using this method is if you happen to have one of those "squirley" spots exactly where your throat is going to be. What ever this spot runs out will be magnified by the time it gets all the way out to the muzzle end. This can happen quite often in Benchrest, where we often have to cut the chamber end off as much as 3+ inches in order to get the barrel profile at the correct weight.
In reality, this is no big deal. One of my best friends has been setting up barrels this way for years, and his Rifles take a second seat to no ones. He doesn't indicate the barrel in the same manner, but he does indicate that first portion that will influence the reamer.
All I do is establish two points that I want to run dead true, and then I single point bore the part that runs out true with those two points. In the case of a barrel, those two points happen to be the muzzle, and that part of the ID where the throat will form, more or less what the bullet "sees" first as it enters the barrel.

As I stated before, the reason I like my method is it allows me to set barrels up very quickly and efficiently to set them back, which is a big part of my over all Competitive Program. I always have the originol reference points to which to indicate the barrel back in.
This is Machinist Stuff. I am sure Gordy, and other shooters out there who have considerable Machinist Skills, understand this.
As I have said, it makes no difference how you do any of this, as long as the operation produces the tolerances and requirements that the finished piece demands. ..........jackie

Lucky Shooter
01-21-2008, 02:52 PM
Both of you gentlemen advocate having the bore at the throat and chamber run true with the bore at the muzzle.

I understand why you want this but I don't understand how you can depend on achieving this----without a barrel with minimum bore curvature or without the possibility of trimming the barrel in search of throat and muzzle locations that will line up.

I think I fully understand how to locate and ream the chamber and how to crown the muzzle square to the bore as independent operations but the alignment of these two points with each other remains a big question for me.

I once considered that you might be making compromises by having tolerances loose enough to approach alignment but now think this is way off----when you work to .0001" tolerances, you can't be making much compromise.

I'm not a cook book and recipe guy and prefer to understand a job from end to end before starting, if possible.

I'd appreciate any clarification you can provide on how to achieve this.

A. Weldy

PPP MMM
01-21-2008, 04:11 PM
Shoot well
Peter

RoyB
01-21-2008, 04:32 PM
It would seem to me that the method Gordy uses to indicate a short section of the bore, perfectly true to the center of the lathe would really pay benefits at the muzzle.

If you simply indicate at one point in the muzzle, the "hole" could still be somewhat out of true with the center of the lathe. When the cown is cut in this set up, it could be at an angle to the bore.

By aligning the bore at two points, in the very least, your muzzle crown will be perfectly perpendicular to the bore.

I'm not sure I would want the involvement of having to set a barrel up to "point up"...But I understand the reasoning, and it's a good one.............

Next barrel I'm going to try this method, but for now I'm certainly incorporating the muzzle set up...........

Thanks Gordy...............Great bit of research there!

Spott3r
01-21-2008, 05:02 PM
Jackie,

It will be interesting to hear your comments after you have seen the Video in its entirety.

-John

jackie schmidt
01-21-2008, 05:21 PM
When I say indicate two points, that is what I mean. The two points that are indicated are no wider than the contact area of the indicator stylus, which, by the way, is round.
No matter what you are truing, you can always arrive at two places that are dead true with each other, and turning true with the axis of the lathe spindle, regardless whether the piece is straight or crooked.
It is when you intruduce the third point is where the problem lies. That is why we establish the "third" point with the single point boring.
From reading some of the comments about this thread, I can see that many of the posters do not understand basic machine shop practice. This is particularlly evident when they cannot seem to understand that if you indicate two points in at the chamber end about 2 or 3 inches apart, there is absolutly no way that the muzzle end can run true, unless it was dead true with those two points in the beginning. And, trust me, unless some miracle happenned during the initial deep hole drilling, it wasn't.
One of the basic tenents I try to instill into young men that I have taght the Machinist Trade to is that to be a good crafsmen, it simply not good enough to know HOW to do things. The true craftsman must learn WHY you do things. Then you can relate basic practices to all endevours.......jackie

Butch Lambert
01-21-2008, 05:38 PM
Jackie,
I think without a classroom setting, the non machinest will not understand what you are saying. I am not saying this to aggravate anybody, but until you have a complete vision of what's happening, you will not understand what Jackie is saying.
Butch

Lucky Shooter
01-21-2008, 06:41 PM
I now fully understand what you have posted.

Its been about 25 years since I did any lathe work and my skills are pretty stale but I still have a good practical understanding of 3-D geometry. I'm very confident that I know and understand how this should proceed and that's a relief.

I'll chamber a barrel when my machine work gets back up to par.

Thank you so much Jackie.

A. Weldy

Spott3r
01-21-2008, 07:10 PM
Jackie,

With respect.

The 'why' is what makes me continue to ask you the questions.

Here's where I believe I am. I actually believe I understand the 'why' you are talking about.

When you said,

"No matter what you are truing, you can always arrive at two places that are dead true with each other, and turning true with the axis if the lathe spindle, regardless whether the piece is straight or crooked."

When you said,"..with the axis if the lathe.." you actually meant "is" and not "if". Correct?

Now, let me agree that there are many ways to do this. Each having seemingly more common sense than others.

The muzzle for you is then related to the chamber position. The muzzle run-out position would be best indexed to 12 o'clock high or for some 6 o'clock low. Never at 9 or 3 o'clock. - that makes sense, yes?

Can you restate your method in shorter simpler terms? I am honestly interested in it.

-John M. Paton

jackie schmidt
01-21-2008, 07:15 PM
I need to get myself another proof reader.
The word is "OF", not if, or is. The sentence should read,....."and turning true with the axis of the lathe spindle".
I have edited and corrected that.
As for muzzle indexing, It is my opinion that this is another solution to a problem that does not exist...........jackie

RoyB
01-21-2008, 07:37 PM
But if you set up a barrel as Gordy does, you will need to index the finished barrel either up or down, otherwise the gun will be shooting at some strange angle away from the centerline of the action and the scope mounts would need a bunch of windage adjustment to compensate. As Gordy says, indexing the barrel "up" is good for long range shooting. I suggest he means the gun will actually shoot high in this situation?

Ideally, you would do all this indicating on an unturned barrel blank, and when all the chamber work and muzzle work was done, then the barrel could be contoured between centers and get both chamber and muzzle back into the same plane...........

I'm intrigued by all of this............Id like to know how much "misalignment" Gordy is finding as he is dialing in these barrels with his method.......And how much is "too much".....?

PPP MMM
01-21-2008, 07:50 PM
Shoot well
Peter

Butch Lambert
01-21-2008, 08:12 PM
You furnishing the popcorn?
Butch

jackie schmidt
01-21-2008, 08:30 PM
You got it.
I have seen shooters who use the indicating method described in Gory's Video have barrels print as much as "off the paper" from one barrel to the next.
I feel safe in saying that every barrel I do will print within 4 inches of the one before when I screw it on. Or at least, that is the way it has been........jackie

jackie schmidt
01-21-2008, 08:31 PM
You lost me on that one. I don't have a clue as to what you are talking about.........jackie

warthog
01-21-2008, 09:02 PM
I am very happy, that people can come to understand that we all don't like milk. I would like to think of a barrel as a line that never ends. If you do so, one could say that only one end of the barrel would be under control at a time. If this is true don't worry about what the other end is doing,as long as your setup is not lost I.E. chamber looks down bore X crown mirrors its own exit. If spider end wobbles much then your set up is to tight at chuck end and one could say that you are flexing the barrel. The way to stop this problem for what it is worth would be to have a gimble setup that is narrow enough to let barrel dial in with out flex on far end, I.E. jewell scope rings would be a good place to look to understand. But these gimbles are much wider than a barrel can take under the load a chuck. Dialing in at two locations at the same time would keep one from having wobble on one axis that is why you use a range rod,but if barrel is flexed this will not work. Always ask what does the earth do while spinning on it's axis, it wobbles Write me back tell me that you would like to know what planet I live on,but don't talk about my spelling by now we all know that I am just a farmer that has a hard time finding the hog lot. Results count make sure to do your barrel work your way!!

JerrySharrett
01-21-2008, 09:15 PM
Both of you gentlemen advocate having the bore at the throat and chamber run true with the bore at the muzzle.

I understand why you want this but I don't understand how you can depend on achieving this----without a barrel with minimum bore curvature or without the possibility of trimming the barrel in search of throat and muzzle locations that will line up.

I'd appreciate any clarification you can provide on how to achieve this.

A. Weldy
For the chambering;

I first determine where I want the muzzle based on barrel taper and the weight I need. eg LV, HV Max HV, etc. I use Dan Lilja's program to calculate weight if I am not duplicating a previous barrel.

I cut the barrel off at the muzzle end to about 1/8" of finished length. In setting this up I indicate the barrel OD sticking out of the tail end of the headstock. I am using a South Bend Heavy 10 so I can work a barrel through the headstock down to about 18" long. On the muzzle end, I indicate the OD at the cut point.

Some barrels will have concentricity errors from OD to ID as much as 1/16". Not a problem. I'm not working in the ID just yet, just cutting the muzzle end to near finish length.

I then turn the barrel around and indicate the OD on the chamber end and a gage pin in the muzzle end. Then cut to approx length with a parting tool just as I did for the muzzle.

At this point with the barrel spinning about 200 rpm I look down the bore to see how much curve is in it. Over the years I have had to send 2 barrels back that I thought runout was excessive. Both looked like a girls 2-girl jump rope. I don't reorder from them again.

Now, with a snug fitting gage pin in the muzzle end I position a dial indicator on that gage pin. I use an Interapid 0.0001" dial indicator with a probe long enough to reach the chamber neck area. I then dial both ends in. The muzzle end I dial in to the nearest 0.001" using the spider. I dial the chamber neck in to 0.0000" or as near that as I can get.

I rough the tenon to about 0.01" over finish size and to length. I pre drill the chamber body to about 1/64 under chamber shoulder/body finish size and almost to the finish shoulder (leave about 1/32" or so for the reamer shoulder to finish.

I then reindicate the muzzle end and the chamber neck. Didn't move so I go on. On the chamber neck I indicate the lands. That's where the neck pilot rides.

I bore the drilled hole to about 0.005" under the shoulder finish diameter then step bore a couple more 0.005" steps in the larger part of the chamber body taper. I don't try to taper bore the chamber body. Too many places to screw up oncluding cutting a surface the reamer will grab on. In most chambers the reamer pilot is already in the barrel bore anyway.

I rough the barrel cone if it is a cone bolt or the counterbore if it is something like a Rem 700.

Finish the tenon OD and shoulder. Make sure the shoulder is very square and no corner radius with the tenon OD.

Finish the chamber gaging off the tenon shoulder. I use a floating pusher that is shown in several posts on this forum.

Finish the barrel cone and thread.

Turn barrel around and indicate the muzzle ID with an Interapid indicator. On the muzzle end I indicate the grooves because I sometimes put a 0.005" x 45 bevel. I have also indicated the tenon OD in this same setup.

When I finish a barrel it will be on paper to within +/- 2" at 100 yards from the barrel I just took off if that barrel was done by me.

Hope I didn't miss anything, Don't try to nitpick this or I will ignore you. If you have a reasonable question I'll try to answer.

Don Nielson
01-21-2008, 09:44 PM
How many nits can a nitpicker pick?

Sorry Jerry couldn't resist. Pumpkin

alinwa
01-21-2008, 09:53 PM
if too many nit pickers pick nits it'll be a nitpickers picnic!

warthog
01-21-2008, 11:28 PM
Sense were picking fruit of the beaten path. How would some people feel about a cnc reamer holder for a lath application. One that has thrust,needle and ball bearings. One that preload is adjustable has 3/32 radial X 2 deg angle properties . One can get this from Kennametal with correct taper for tailstock .

Lucky Shooter
01-21-2008, 11:31 PM
Just wanted to thank you for answering my post.

You and Jackie have cleared the fog for me and I appreciate it.

A. Weldy

JerrySharrett
01-22-2008, 05:29 AM
How many nits can a nitpicker pick?

Sorry Jerry couldn't resist. Pumpkin
Don, I was thinking as I was typing that, I shouldn't have said it that way.

Then after I posted it, I reread it and said I should remove that sentence.

But, then I thought, "what the 'ell"!!

BTW, how many nits can a nitpicker pick?

You too Al!!!

Rustystud
01-22-2008, 05:54 AM
I was fortunate enought to get a copy of Gordy's DVD. I watched it intently. I have the greatest respect for Gordy. His work speaks for itself. Having chambered rifles off and on for 35 plus years I have learned to have an open mind. I have said it many times that I learn something new every day. I took notes of the differences in how Gordy and I chamber. I have watched this post very intently. I think that I chamber more like Mickey and Jackie, and Mike Bryant not that my skills are anywhere near their levels. I was glad that I was not the only one who had questions about some of Gordys methods. I have several customers who have several barrels made and chambered at the same time. One particular customer has 25 barrels chambered all at one time. I am going to ask him is I can experiment with the two different methods of chambering with him conducting a blind test. My customer shoots extremely well and is a great records keeper. I will ask him to report to me the results of his barrel testing. This time next year I will have tested both indicating both ends to dead center or just aligning the chamber end and aligning the muzzle up.

Nat Lambeth

RoyB
01-22-2008, 07:05 AM
Nat,

You would have to chamber a bunch of barrels both ways to get a reliable statistic on what method works better than the other. Something like 200 barrels should do (of each chambering method!)

With just two barrels there are infinite variables that will negate any results.

I still contend, using Gordy's method on the muzzle will reap more benefits, without any negatives. This is where the bullet meets "free flight" and how it is released by the crown will effect accuracy. Just look at what an improvement simply recrowning a barrel makes..........Having the crown 100% perpendicular to the bore (at least for the length of the bullet, just has to improve accuracy. I'm going to take a couple of my real good shooting barrels and recrown them with this method just for kicks and giggles and see how they shoot.............I too keep pretty good records on my target barrels, and only changing one variable on a know performing barrel should give reasonably good information.

But the whole chamber end of the barrel being out of align with the receiver face just seems more work than the dividends it will pay. If a tight fitting range rod will enter the chamber end of the bore to a distance of lets say, 4" without binding because of excessive "bore twist", I would say you are good to go with Jackie's method. If the barrel has a bad bend at this critical area, I'd return the barrel...............

Joe Ponto
01-22-2008, 12:47 PM
Does anyone know if Gordy is selling these DVDs? I called Grizzly and they informed me they do not ship to Canada... :confused:

Always looking for excellent resource material.

Regards,

Joe

Please pm me...

Dusty Stevens
01-22-2008, 01:39 PM
I like to look at match results for indication on a gunsmiths ability

Jefferson
01-22-2008, 02:09 PM
I called and they said they cannot ship to canada as they have a deal with another manufacturer to stay out of canada.

then another person said our minimum order for the DVD to ship to canada is $200

maybe they would like to respond. we are not a 3rd world country and should be able to get the DVD around the same price as usa folks.

(I guess a call to one or more of the vendors we deal with cound result in getting the dvd to canada but we would prefer to deal direct)

Jefferson



mmmmmmmm maybe Joe can be the official importer and make a lot of money mmmmmmmm

J. Valentine
01-22-2008, 03:35 PM
Thankyou Jerry Sharrett for taking the time and effort to tell members how you chamber.

Gordy Gritters
01-22-2008, 05:55 PM
But some of you are making this seem considerably more complicated than it really is. Doing it this way like we show in the DVD (please buy the DVD from Grizzly before you criticize this method too much) perfectly aligns the receiver to the chamber and to the beginning of the bore, and the muzzle is only ever so slightly offset to achieve this. The barrel still fits the barrel channel almost exactly the same, and there is absolutely nothing "crooked" about it. It works great - every single time without fail!

Roy B asked earlier about how much misalignment I'm seeing when I set up barrels this way, and how much is too much. Looking at my records for the past 2 years, the muzzle runout in benchrest barrels was anywhere from .003" to .031", with most barrels in the middle of this range, which isn't very much at all. I've seen hunting barrels as far out as .100" (quite rare) and once had one that was over .200", but I send them back if they go over .060" or so since I don't really like to see that much. I really have not seen any problems with accuracy with barrels anywhere in the .040"-.050" or below range, which almost all benchrest quality barrels are. I find quite a bit more problems when I slug and evaluate barrels as I get them from the manufacturers and I send them back when they show bore dimension problems - again this is rare with high quality benchrest barrels though.

If I am doing a barrel for a glue-in (which I seldom do anymore), I don't worry about trying to index the muzzle up or down (it will still shoot great without indexing it), but I definitely still align the chamber to the first few inches of bore ahead of it like I do everything now. I started to index muzzles "up" with the 1000 yard guns to get a few more (very few usually) minutes of elevation adjustment for some of the guys whose scopes were limited on elevation adjustment range. Even with the barrels that have the muzzle .030" or so out, this only makes for a very slight difference in windage or elevation, but for long range shooters I want as much elevation capability as I can get. If it's "off the paper" like someone said, that is a bad barrel, not a problem with doing it this way. I also like the idea of the weight of the barrel at the muzzle to be up or down, not at 3:00 or 9:00 if I can help it.

Somebody also mentioned about how this affects crowns. It doesn't matter which way you indicate the barrel in, the crown will be cut straight to the centerline of the lathe, just like the chamber would be - that's just basic machining. But in my opinion, no matter how much we may want it to be otherwise, if you indicate both ends of the bore to be running true at the throat and the crown, the bore WILL be curved in between those 2 points, and the bore WILL be coming down to the chamber and the crown at a slight angle, which I don't like to see. Just like at the chamber end, if you indicate the last 2 inches of bore before the crown to run straight and true, the crown will be cut just a little straighter to the bore (90 degrees as opposed to 89 3/4 degrees for example).

There is no question that guns will shoot extremely well done either way as we all know, but in my opinion I just feel it gives a slight edge doing it the way I do it now, and anything I can do to gain any edge at all I am going to do! Like I said earlier, since changing to this method my percentage of "so-so" barrels has noticeably gone down and the number of "hummers" has gone up.

Someone also asked if I'm selling these DVD's since they live in Canada. I'm sorry, but I'm not selling them at all - that is all done through Grizzly at this point. Not sure how to get them to Canada - maybe if you know someone coming to the SHOT shot, they could pick one up for you there.

Gordy Gritters

alinwa
01-22-2008, 09:38 PM
Thank you Gordy.


al

Joe Ponto
01-22-2008, 10:25 PM
Gordy, please put me down for one DVD at the shot show. Can you hold one for me. Will see you there!

Regards,

Joe
RPS International Inc.

Jefferson
01-23-2008, 12:06 AM
thanks GG for answering the question. look forward to watching you at work.

Jeff

Don
01-23-2008, 03:18 AM
[QUOTE=RoyB;379427]
Ideally, you would do all this indicating on an unturned barrel blank, and when all the chamber work and muzzle work was done, then the barrel could be contoured between centers and get both chamber and muzzle back into the same plane...........

QUOTE]

Hi Roy,

Actually, it is not the cutting of the chamber and muzzle in Gordys method that would potentially set the muzzle off center to the stock alignment with a wandering barrel bore, but the cutting of the threads and shoulder in the same setup as the chamber cut which are the key elements in determining position.

No amount of re-contouring between centers after the thread and shoulder have been cut, will bring the barrel back into alignment.

My chambering method and results are almost identical to Gordys except for slight variations in the use of range rods, which is strictly an ease of setup variation.............Don

Gordy Gritters
01-23-2008, 07:47 AM
Joe, will do. If for some reason we don't get together at the SHOT show, let me know and we'll get one up to you somehow right after that. Looking forward to meeting you there!

Gordy

JerrySharrett
01-23-2008, 09:32 AM
Like Gordy says, Greg Tannel has a possibly workable holder. Greg does a lot of really good work.

But as to the run-of-the-mill floating holder here is what Greg says about them;

""Helpful hint: If you don't know how, or your tailstock simply can't be realigned, then one of the manufactured floating reamer holders on the market is what you will need to purchase to correct axis misalignment and give you the ability to ream straight chambers. But, on a floating reamer holder, nothing guides the back of the reamer, it goes where it wants. If the reamer starts crooked, it stays crooked, no matter how the barrel is lined up. It's up to you, my system where you know you're straight, or the others where you hope you're straight. "" http://www.gtrtooling.com/prod09.htm

This is why I think a floating pusher is best in all cases, trued tailstock or not.

The main problem with pushing with the tailstock center engaging the reamer center, it doesn't matter how much you level and re-level your lathe. If it is set on Gods earth, concrete floor, isolated base, etc. it is going to move, from now to ever more.

I've run too many tests with laser alignment equipment built special to align machine tools and steam turbines. Anything set on this earth is going to move, its just a matter of when and how much.

cdog
01-29-2008, 04:45 PM
Gordy,
Are you saying that Grizzly will have the videos for sale at the shot show?
I know of a few guys from here(Canada) that are going, and I would get them to pick one up for me.
Thanks in advance,
Cdog.

col48
01-29-2008, 05:08 PM
hi all

i have been trying to get a copy of this DVD,but i can not get one sent to the UK,as there is a minimum order of $200
shame
ATB
Colin

chino69
01-29-2008, 06:39 PM
All I can say is that I am totally lost. I've been looking for an excuse to buy the video so it looks like that will be the first order of business, followed by trying to understand what you fellows are discussing, and hopefully learn something in the process. If I'm not successful in this endeavor, the looming attraction of women of ill repute and strong drink may just overcome my curiosity; returning me to my former habits.
Chino69

p.s. Seriously, I can't think of a better way to keep one's mind sharp than reading some of the threads on this forum. It's kind of like going to gunsmithing lectures from the comfort of one's own home. Thanks to all you fellows for sharing your knowledge.

cdog
01-29-2008, 08:10 PM
Chino, if you need a reason to buy a video, you can mail me one!!!
I would certainly pay in advance, and pay any extra shipping charges, and even some extra fer a bottle of mind-numming solution!
It seems I'm running out of options on this. I can't beleive i'ts that hard to get a foolish video to Canada, grrrrrrr!!!!
Cdog.

Butch Lambert
01-29-2008, 08:22 PM
Gordy,
The picture that you drew on the video with the reamer going in crooked is not true if you indicate the throat and drill and bore to that point.
Butch

Gordy Gritters
01-29-2008, 09:24 PM
Cdog,

I know Grizzly is supposed to be bringing a bunch of DVD's to the SHOT show, so hopefully someone can pick one up for you there. I'm not sure why they can't send the videos out of the country yet - but they've run into some legal red tape over it somehow, I think (post 9-11 gun paranoia at the border, maybe?).


Butch,

It actually does work exactly like I show in the drawing, although I greatly exaggerated what was going on in the drawings so people with all levels of expertise could hopefully understand what I was trying to show them - I know I'm not much of an artist, but I tried to make the drawings as simple as I could. What I maybe should have done was shown the reamer/chamber in the barrel instead of outside it like it would be before starting the chamber- maybe that would have made more sense to you.

The reamer is not really crooked like my exaggerated drawing makes it look like- everything (chamber, threads, receiver) is just being aligned to the centerline of the bore at that end, and the bore right ahead of the finished chamber will be lined up perfectly to the chamber also, which is the most important part.

If you have a bore with some curvature to it, which all barrels do, and you indicate it to run true at both ends of the bore - at the throat and the crown - the bore will be curved in between those two points. So if you indicate it at the throat, drill and bore, then chamber to that dialed in throat, the bore coming to that throat will be curved and on a different plane than the chamber.

Next time you chamber a barrel that way, when you are done, test this by running a long reach indicator in and measure at the rear of the chamber, the front of the chamber and the throat. If you've done your part all those parts should have zero runout and be running true.

But don't stop there, now keep moving the indicator forward past the throat up the bore a ways ahead of the chamber. Depending on how much curvature that particular barrel has, you will IMMEDIATELY start to see some bore runout. Sometimes this shows up quite well in as little as 1/4" to 1/2" into the bore ahead of the throat. Long bullets aren't even clear out of the case yet and they are having to turn ever so slightly to get lined up to the bore when they are starting into it.

You can clearly see on the DVD when I am done with the chamber I do exactly that test. Not only is the whole chamber, front and rear, running perfectly straight and true, the bore ahead of the chamber a ways is also running perfectly straight and true with absolutely no runout. I have never been able to achieve that until I started to dial bores in like I do now.

Hope this explains it!

Gordy Gritters

JerrySharrett
01-30-2008, 05:57 AM
But don't stop there, now keep moving the indicator forward past the throat up the bore a ways ahead of the chamber. Depending on how much curvature that particular barrel has, you will IMMEDIATELY start to see some bore runout. Sometimes this shows up quite well in as little as 1/4" to 1/2" into the bore ahead of the throat. Long bullets aren't even clear out of the case yet and they are having to turn ever so slightly to get lined up to the bore when they are starting into it.

If you are setting up on a curved bore, using any method, the curvature of that bent cylinder will immediately start leaving the straight line drawn through the centerline axis of the chamber. Fact!!

Gordy Gritters
01-30-2008, 08:07 AM
Jerry,

That is absolutely right. The whole length of the bore is a continuous curve from one end to the other, some more so than others. But the amount of curvature in 2-3 inches of most bores is almost not detectable if that part of the bore is running true to the centerline of the lathe, and it is much more easily detectable when dialing in both ends of the bore.

When you set up with the bore running true at both ends, the curvature ahead of the chamber/throat is immediately apparent when going forward from the throat with a good indicator. But if you align the chamber to the first few inches of the bore like I show in the DVD, you have to go several inches ahead of the throat before you can start to detect this curvature.

The next time you chamber a barrel, just try this simple test. After you get both ends dialed in and running true at the throat and at the crown, take your test indicator (or use a range rod to reach further in if your test indicator won't go far enough) and go just 1" ahead of the throat and see just how much runout there is. Unless you have an exceptionally straight bore, the majority of benchrest quality barrels (from any of the major barrel makers) will show a noticeable amount of runout compared to where the throat is.

I noticed this a number of years back already when I used to dial in barrels at the throat and the crown like so many of you still do, and when I saw just how badly doing it this way aligned the throat to the bore ahead of it, it really bothered me. I continued to experiment to try to find a better way to align the chamber to the bore, and right now I've never found a way to do it any better than how I show in the DVD.

Believe me, I am never "married" to any way of doing anything - you cannot improve if you do not have an open mind and a willingness to make changes to improve how you do something! If I can find a better method of doing something in some of my experimentations (which I do constantly) or if someone else has a method of doing something I have not tried yet, I try it, test it thoroughly, and if it works better than the way I do something, I immediately change.

Thanks!
Gordy Gritters

JerrySharrett
01-30-2008, 08:31 AM
The whole length of the bore is a continuous curve from one end to the other, some more so than others. But the amount of curvature in 2-3 inches of most bores is almost not detectable if that part of the bore is running true to the centerline of the lathe, and it is much more easily detectable when dialing in both ends of the bore.
Wrong Gordy my friend. The wanderings of a gun drill does not make a continuous curve. I call that curve a "compound curve" from my old highway surveying days but I'm not really correct there either. A compound curve is a curve where the radius is continually changing. In the barrel bore situation there is a 3-dimensional wandering.

The barrel just ahead of the chamber may, I say may, be perfectly straight for some distance. Or, it may make an immediate curve to the left, then immediately wander off in another direction.

If your prediction was correct in that you are lining up on a continuous curve, I would feel better about your alignment method. But is is not, in most cases, a continuous curve. I just feel better if the bullet exits the barrel in alignment with the action/stock that is is ejected from.

From here on out it is just a pi$$ing contest. Have fun at the SHOT show.

flatlander
01-30-2008, 09:03 AM
We're leaving for the SHOT Show early Friday morning - it's a 1000mi. drive, and right now, I'm hoping to keep my simple mind on the driving. If I start cogitating on all the points brought out in these six pages of posts, I'm liable to get hurt. Actually, I'm really looking forward to meeting Gordy at the show, buying one of the DVDs, and getting a close-up, hands-on look at Grizzly's lathes.

For the record, there are only 31 cut-off stubs from barrels I've chambered over the past two years since I started doing barrel work, so I'd classify myself as a rookie with a lot to learn. Currently, my set-up method follows Jackie's as closely as I can manage, including drilling & boring to rough the chamber. Finished chamber runout has improved measurably since I started roughing this way; if Gordy's methods can improve the consistency of the quality of my barrel set-ups, I'm all eyes & ears.

Shiraz Balolia
01-30-2008, 09:27 AM
From here on out it is just a pi$$ing contest.

That's exactly what it is! People trying to prove Gordy wrong, or to prove their methods are better, or that they are a better machinist.

Frankly I don't care how he chambers, but I can tell you from first hand experience - I love the rifles that Gordy chambers for me. If the barrel slugs good, it really shoots well. I have won numerous 300 yard matches, come close to setting a National record (by one X) on a 20 shot string and placed well in the Nationals shooting at a thousand yards (and I have only shot 1000 yds twice). His guns have set National records by other shooters. The proof, like another poster said, is in the match results. God forbid......he must be doing something right!

Butch Lambert
01-30-2008, 09:48 AM
Shiraz,
I am not taking to task his method or success. I'm just pointing out that indicating the throat, drill, and bore will have the reamer started coaxially with the centerline of the headstock bearings. The reamer will not start at an angle shown in the video. If you just ran the reamer in without the other operations, I could see a problem.
And yes, if My Clausing gives me trouble, I'll look real seriously at your lathe.
Butch

Joe Ponto
01-30-2008, 10:25 AM
Folks I just want to thank all of those who have shared their methods and experiences. Thank you. The information is extremely valuable and offers people the opportunity to see and understand different ideas and findings. In some cases it supports current methods and in some cases it offers points that we might not have considered. Excellent thread....

JerrySharrett
01-30-2008, 02:25 PM
That's exactly what it is! People trying to prove Gordy wrong, or to prove their methods are better, or that they are a better machinist..
I didn't see this thread as that at all. I saw the discussion as being among gentlemen who have considerable barrel fitting experience. I've read it as discussing methods and pointing out the pros and cons of each method. In my situation I respect Gordys opinion and I hope he respects mine and I sincerely feel he does.

I think there are many people new to benchrest barrel fitting that have gained better insite with this discussion. I hope so anyway. How we get better at what we do is not all by trial and error, much of it is brought on by the exchange of ideas.

Gordy Gritters
01-30-2008, 04:39 PM
Anyone who knows me at all knows that I do not take offense easily to much of anything. I know people all have opinions based on their past experiences, and that sometimes when something new is presented it can be a little hard to understand or accept a new concept without some questions, and I'm fine with that. That is one nice thing about these forums, when these questions are raised others can benefit by "pushing their understandings" at the same time, like Joe Ponto pointed out.

One thing I do want to comment on is the concept where some of you apparently think that barrels can have "immediate curves" or veer suddenly off in different directions. All the curvature I've ever seen and measured in a barrel is extremely slight and always extremely gradual - nothing sudden about it. Normally never over about .035" over the whole length of the barrel. When you dial one end of a bore to run true, you have to go several inches up the bore before you start to measure the curvature beginning - the more curvature in a particular bore, the quicker you can start to see this happening . However, if the bore has a fair amount of curvature, and you have it dialed in to not account for this curvature, the curvature right ahead of the throat can show up very quickly and make it seem like there is a sudden change. But this is caused by the chamber not being in alignment to the bore at that point.

I am thoroughly aware that the curvature in a bore is not always a "straight" curvature, but almost always has somewhat of compound feature to it like I mentioned in an earlier post. This is so gradual and so slight, that I've never found it to be any problem at all, and rarely mention it to people when trying to explain this concept since it just causes more confusion than it needs to. When I index the muzzle end in the "up" position, it shoots just a little higher every time like I want it to.

Butch, I'm not sure why you are thinking the reamer is starting at an angle - it's not. Maybe because it's being lined up to the bore and not to the outside of the barrel, which aren't usually aligned to each other. The reamer is being pushed straight by a lathe center on a perfectly dialed-in lathe - it has to run straight. Plus it is being fed into dialed-in bore that has been bored true to the lathe, and the bore ahead of that for the next couple inches is also dialed-in to be aligned straight. Everything at that end is aligned straight and true to the lathe - nothing crooked about any of it.

Just please test this like I mentioned in yesterdays post and hopefully you will see what I'm talking about.

Back to you guys.....:)

Gordy

Butch Lambert
01-30-2008, 06:22 PM
Gordy,
The problem that I have with the internet is people like me have trouble expressing ourselves properly. The other thing is our emotions may come out in a way not intended. Whether I agree with you or not, the video was as good as any that I have seen on the subject.
Butch

Big Al
01-30-2008, 06:47 PM
If the chamber is concentric to the bore and the chamber is on center with the muzzle. How do it get better than that? I know this may be way to simple, that's probably cause I'm just simple minded.

I will also add that the barrel and receiver threads are concentric to the bore.

I guess I'm missing something here?:confused:

Butch Lambert
01-30-2008, 06:53 PM
Big Al, I don't think any of us disagree with what you are saying. We just have different ways that we think that is best to achieve it. I have my own reasons for doing it a little bit different than Gordy, but I will not state that he is wrong.
I just do it differently than he does. Is that what you are asking? I am just a country boy also.
Butch

Big Al
01-30-2008, 08:29 PM
What I should have written was, what does it matter what you do, to get to the same place we all want to go?:confused:

Butch Lambert
01-30-2008, 08:35 PM
Not a thing. I started the post to get others opinion and ideas, not to tell Gordy or anybody else that they were wrong.
Butch

Big Al
01-30-2008, 08:57 PM
While I admit to be one of the guys that set and read what others do and wonder why they go the long way around to do a job that is fairly simple and straight forward.

I just don't think that the guys that throw a lot more money in tooling are wrong. I just figure they have some special circumstance to overcome.

Heck we are all human, and deserve a little freedom (until the next election anyway). To pick and choose, how we do a job, is one of them. Just because I think the other guy is doing something different, that's a waste of time, You got to keep in mind, it's his time.

I'm did not write this with Butch in mind, I wrote addressing everybody.:)

tim in tx
01-30-2008, 09:08 PM
i have to say a few weeks ago i was pondering ,just getting to the vital area in front of the chamber without pre cutting some metal away just to get to the throat to measure with my test indicator,i was told by stick you had a dvd showing a new centering method, when i heard of it and now that i have seen the dvd , that is the best way i have seen yet to measure anywhere in the bore before even taking a cut on it it sure cured my problems.i dont think anybody say they can even reasonably measure a spot 4 or 5 inches into the bore before cutting via any other method.also makes for a nice bushing holder to check the fit 4-5 inches in as well your vidio helped me and i thank you for that sir. and great thread as well good ideas are a flowin. tim in tx

Joe Duke
02-01-2008, 02:30 PM
Mr. Gritters, How long is the range rod you are using and where did you acquire it?
Thanks for all the good information you have shared here.

Joe Duke

Chisolm
02-01-2008, 03:09 PM
Joe
I'm not Gordy but I would guess that he is on his way to the shot show.
Since I got this information from Gordy I'll pass it along.

Gordy makes his own rods using 12" long drill rod.

I use three different size drill rod for the three main ID of reamer bushings -13/64", 15/64" and 17/64" if I remember right.

I had some brass rod on hand so that is what I used to make mine and they turned out very well. I drilled and tapped the end of the rod to use a 6x32 screw to hold the bushing on the rod.
I fitted the bushing by turning a little at a time and trial fitting the bushing on the rod until it just slipped on and rotated freely when well lubed.
If you don't want to make your own you might try contacting Dave Kiff at Pacific Tool and Gauge. I know Gordy discussed having him make some.
James

Butch Lambert
02-01-2008, 03:37 PM
You could use a spin collett fixture on your surface grinder to get the size perfectly.
Butch

tasy_ted
02-01-2008, 09:42 PM
hi guy's
i do not see a pissing comp here. what i do see is a lot of
good gunsmiths and machinest's trying to make the best chamber/barreling
job that they can. and in that you are all united.
i have found that this is a very well informed thread.:D:D

regards ted

Bnhpr
02-02-2008, 07:45 AM
You could use a spin collett fixture on your surface grinder to get the size perfectly.
Butch

Could a PTG indicator rod be modified for this task?

Was thinking about grinding one down with a tool post bench grinder, behind the pilot?

Chisolm
02-02-2008, 09:45 AM
Could a PTG indicator rod be modified for this task?

Was thinking about grinding one down with a tool post bench grinder, behind the pilot?

I think the standard PTG indicator rod would be too short.
If you are going to turn down the PTG indicator rod, why not just make your own indicator rod out of drill rod like Gordy does?
James

Bnhpr
02-02-2008, 01:46 PM
I think the standard PTG indicator rod would be too short.
If you are going to turn down the PTG indicator rod, why not just make your own indicator rod out of drill rod like Gordy does?
James

I would not mind making making one, but drill rod can be tough to machine.

I just don't understand why you need to reach up into the barrel 10 inches. I watched the video, and Gordy seems to indicate, the significant part of the barrel, to align the chamber to, is the first 6 inches?

alinwa
02-02-2008, 02:30 PM
bnhpr,



It ain't about REACHING 10" into the bore it's about having enough shaft OUTSIDE of the bore for flex and for taking readings. I've actually considered making them 16" long, thinking that 12 was so short that the rod may have some resistance loading......


This range rod application more than paid for the vid IMO, O'l Gord's a perty fart smeller yeahhhh........yup. And from Ioway no less......a state where most of the folks have been sold to believe you can make gas from corn :D:D:D


(I spent 17yrs in Min'desoda Gordy so you'll have to excuse me ;) )

Bnhpr
02-02-2008, 02:34 PM
bnhpr,



It ain't about REACHING 10" into the bore it's about having enough shaft OUTSIDE of the bore for flex and for taking readings. I've actually considered making them 16" long, thinking that 12 was so short that the rod may have some resistance loading......


This range rod application more than paid for the vid IMO, O'l Gord's a perty fart smeller yeahhhh........yup. And from Ioway no less......a state where most of the folks have been sold to believe you can make gas from corn :D:D:D


(I spent 17yrs in Min'desoda Gordy so you'll have to excuse me ;) )

Ok, that makes sense. Any tips on making the rods, dimensions or pics?

alinwa
02-02-2008, 02:42 PM
No, not from me as I haven't made one. I hope though that someone does post on it as it isn't as easy as it would seem without a toolpost grinder.


For us newbies :)


al

Chisolm
02-02-2008, 04:12 PM
Al is correct in the reasoning for making them 12" long.
I had originally planned to make mine 18" long but after talking to Gordy decided 12 was enough.(Al a measured 12" not what you been telling your wife is 12"):D.
I thought I had taken some pictures of the ones I made but can't find them, I'll ty to take some and post them.
One of the reasons I went with brass rod was the machining concerns you guys have and I had it on hand.
I drilled the end before turning it down then ran a live center on the end and cucked it in close to the chuck to prevent flex. I turned them down to the point the bushing would almost fit on then pollished until they did fit.
I didn't do any measuring as I wanted the bushings to fit as tight as possible without them being "grabby" but turn smoothly and I figured I could get them closer by fitting than measuring.
James

Butch Lambert
02-02-2008, 04:32 PM
I haven't noticed that drill rod was hard to machine. It will work harden though. If I were to build one, I would borrow a screw out of one of my reamers to check size. I would put it in a collet to drill and tap. I would put it in my spin collet and put it on my surface grinder and grind to fit the bushing. I have a toolpost grinder, but don't like to use it if I can get by without it.
Butch

Bnhpr
02-02-2008, 05:33 PM
I haven't noticed that drill rod was hard to machine. It will work harden though. If I were to build one, I would borrow a screw out of one of my reamers to check size. I would put it in a collet to drill and tap. I would put it in my spin collet and put it on my surface grinder and grind to fit the bushing. I have a toolpost grinder, but don't like to use it if I can get by without it.
Butch

"SNAP" is the sound small taps make in tough material (like drill rod)

I have a tool post grinder, so I guess I'll order up some drill rod and go for it.

Brass sounds interesting, any problems with it yielding?

What diameter drill rod, for 22 cal and up?

Ben

Chisolm
02-02-2008, 06:06 PM
Using a caliper with resolution to .0002 most readings I get are .0002 smaller than those in the picture. You don't want any slop between the rod and the bushing or more correctly no more clearance than is required for the bushing to rotate on the rod.

http://i128.photobucket.com/albums/p192/james_hx/indirod.jpg

You'll notice that there is a step in the smaller rod I will probably turn it down to .200 the rest of the way down the rod until there is only about 1" left unturned so the rod isn't trying to flex in to places.
James

Chisolm
02-02-2008, 06:09 PM
"SNAP" is the sound small taps make in tough material (like drill rod)

I have a tool post grinder, so I guess I'll order up some drill rod and go for it.

Brass sounds interesting, any problems with it yielding?

What diameter drill rod, for 22 cal and up?

Ben
Ben I saw your post after I posted mine.
The rod on the left is for 22 cal and 6mm.
The one on the right is for 7mm.
I don't know at what caliber the ID of the bushings change.
No problems with the brass yet.

James

tech-shooter
02-02-2008, 07:42 PM
I made my first one out of some 303 stainless 0.250" rod that I had laying around (for the 6mm range rod), and the next one for 6.5mm from 0.250" W1 drill rod. If you look here (http://www.the-long-family.com/tooling.htm) you can see some pictures. Just follow the slideshow in about 5 pics or so.

They are about 16" long to ensure good sensitivity. I machined the bushing surfaces to about 0.0003" over size, then went the rest of the way with a diamond "ez-lap" hone and some 320 grit paper, until the fit was perfect. The 6mm rod was machined down to about 0.232" for the first 8 inches or so. Next time I'll use the appropriate size drill rod and eliminate the diameter reduction step, as you can get it in 1/64" increments, and it machines very nicely.

I tapped the screw hole by holding the tap in the tailstock chuck,and rotating the spindle by hand (carefully), with lots of high-sulphur cutting oil. No drama at all.

Cheers,

jackie schmidt
02-02-2008, 09:45 PM
Drill Rod, before it is hardenned, is certainly not "tough". In fact, it machines, drills, and taps, rather easilly. But Butch is correct, it will work harden due to the high carbon content.
For this "range rod", anything will do, as long as it will go into the ID of the barrel with enough clearance to do the job. The only thing important is the fit of the bushings ID. The more slack the bushing has over the turned, (or ground), end of the rod, the more induced error there can be in the transfered readings. For instance, if the bushing has .0003 clearance, it is possible to start with that much error that is built into the set-up.........jackie

Dusty Stevens
02-02-2008, 11:40 PM
range rods are cheap to buy. certainly cheaper than making one

alinwa
02-02-2008, 11:48 PM
I've got to think this through, BUT................I question this.


"For instance, if the bushing has .0003 clearance, it is possible to start with that much error that is built into the set-up."



I don't know that that's really true Jackie, a small amount of pre-load will ensure that whether you've got .0003 or .003 you'll get a good reading. Even on a reamer pilot this holds true as one flute is sure to be doing SOME more cutting than the others, the end of the reamer doesn't just flop around inside the bushing....


al

Bnhpr
02-03-2008, 10:37 AM
I've got to think this through, BUT................I question this.


"For instance, if the bushing has .0003 clearance, it is possible to start with that much error that is built into the set-up."



I don't know that that's really true Jackie, a small amount of pre-load will ensure that whether you've got .0003 or .003 you'll get a good reading. Even on a reamer pilot this holds true as one flute is sure to be doing SOME more cutting than the others, the end of the reamer doesn't just flop around inside the bushing....


al

Al,

To preload it, you run it of your rest? From your tailstock, it will be kinda centered, i.e., not preloaded, or possible preloaded up or down, maybe not in the axis your indicator is lying?

So, this begs the question, shouly it be run off the tailstock or carriage?

Bnhpr
02-03-2008, 10:42 AM
range rods are cheap to buy. certainly cheaper than making one

Awe heck, making them is the fun part!

alinwa
02-03-2008, 05:06 PM
All's I'm saying is that you HAVE to give it SOME preload simply because you can't avoid it.........just like a reamer it WILL hold to one side or the other. In the case of a reamer this simply means that the reamed hole will be "1/2 of the play out" or in the case of Jackie's example, if you used a reamer pilot with .0003 of clearance then the reamed hole will be at minimum .00015 oversized :)


In the case of the range rod I can't see ANY induced play............after all the long-reach indicator isn't contained at all. You just load it against one side and go.


al

Spott3r
02-04-2008, 01:00 AM
It was really neat to meet Shiraz and see Gordy showing the G0509 with a real barrel in progress.

The G0670 was very neat. As was the G0667X

http://www.grizzly.com/products/9-x-48-High-Precision-Variable-Speed-Vertical-Mill/G0667X

http://www.grizzly.com/products/16-X-40-Electronic-Variable-Speed-Lathe/G0670

Going back Tuesday am for the class for the Gunsmithing School.

Bnhpr
02-04-2008, 09:06 AM
It was really neat to meet Shiraz and see Gordy showing the G0509 with a real barrel in progress.

The G0670 was very neat. As was the G0667X

http://www.grizzly.com/products/9-x-48-High-Precision-Variable-Speed-Vertical-Mill/G0667X

http://www.grizzly.com/products/16-X-40-Electronic-Variable-Speed-Lathe/G0670

Going back Tuesday am for the class for the Gunsmithing School.

The VFD drives are sweet to operate. I bought a Clausing Metosa variable speed last year for work, and it really saves time.

I'm not familiar with the Yaskawa drives, but I have worked with many other drives extensively, and will say that they are becoming very reliable these days.

flatlander
02-05-2008, 09:07 PM
Got home from the show in Vegas just a few minutes after midnight this morning - left Vegas just after 7am CST, then drove in snow from about 90mi. west of Flagstaff to about 20mi. west of Albuquerque. I have to tell you guys, the long drive (2144mi.) was worth it. Lots of neat guns, optics, & other shooting gear to look at for sure, but one of the highlights for me was to meet Shiraz & Gordy and get a close look at those Grizzly lathes.

Gordy spent probably 15min. answering my questions about both the lathe & his methods - I've met a lot of good people over the past 30+yrs. in the shooting game, and there's no doubt in my mind that Gordy's one of the good guys. Shiraz was also very cordial - my biggest regret after getting a good look at the machines at the show is that he didn't have this selection of models available a few years ago when I was looking for a good lathe & mill.

I'm gonna pop myself a big bowl of popcorn and settle in to watch the chambering DVD.

dennisinaz
02-05-2008, 11:43 PM
I got home from the SHOT show a few hours ago- only a 3 1/2 hour drive for me. Every time I went by the Grizzly booth it was swamped. I got to look at stuff for about 5 minutes and talked to Shiraz about the difference between the Taiwan and Chinese models.

Dave Kiff makes two different range rods- one for unchambered barrels and one for chambered barrels. They are $38 plus $8 per bushing. That is cheap enough not to fool with making one myself.

I wish I had gotten the opportunity to talk to Gordy more about the range rod use but it just didn't happen.

Both the G0509G and the bigger "looking" but apparently same size, 670 looked like nice machines and certainly up to the task at hand.

Too bad this thread had to turn into such a pissing match...

Chisolm
02-06-2008, 08:42 AM
Dennis
If Dave is only making 2 indicator rods then he must have dicided not to make the ones that Gordy is using because Gordy's indicator rod is different than either Daves range rod or indicator rod.

Gordy or Dave Kiff, if you see this could you comment on the availability of the "Gordy's indicator rod".

James

Butch Lambert
02-06-2008, 09:07 AM
Dennis,
I don't see this as a pissing match at all. Several opinions came out in this thread. I was able to call Gordy and visit for about 30 min. It was a great conversation.
Butch

Doc Marsh
02-06-2008, 01:39 PM
The Shot Show was great, last time I was there was in Houton Texas 1983! Took my 17 year old son and one of his friends, drove from Phoenix. Spent about a hour over two days at the Grizzly booth #1973. I got to meet Shiraz, a real gentleman, and watch Gordy at work while he was visiting with everyone. I found both Shiraz and Gordy to be laid back and very easy to talk with. Well worth the trip to Las Vegas. My son and his friend found the show to be overwhelming, as did I. Now to sell one of my lathes so I can fit the new 16 x 40 into the shop. Doc Marsh

Gordy Gritters
02-09-2008, 10:51 AM
Just got back from the SHOT show and it went just great out there. I met a great bunch of people and amazingly I didn't even screw any barrels up while chambering surrounded by a crowd:) I really have to say the Grizzly lathes performed beyond what I even thought they would do. I chambered on one for the first time last summer when we made the DVD, and now did three more chambers at the SHOT show - all of them came out perfect!!. It took a little while to start getting the feel of the machine, but oh man did it do a great job- every one came out flawless, even with all the distractions.

Those of you who were there saw that all three barrels I chambered ended up with absolutely no runout whatsoever in the chambers front to rear (the .0001" indicator didn't even wiggle when turning the barrel), even with quite varying amounts of curvature between the three barrels the throats were all perfect, and the runout in the bores ahead of the chambers stayed less than .0001" for at least 2-3" ahead of the chambers before the curvature slowly started to become measurable.

I had a lot of questions on range rods, and I see some of the same questions here after I got back so I thought I'd clarify how I do it. I made three sizes of rods for the main chambers I do: #1 for 22 and 6mm: make from 13/64" drill rod, turn the end down to about .189" and then grind it or spin it down to where the reamer bushings will just barely go on and turn freely. #2 for 25, 6.5, 270 and 7mm: use 15/64" drill rod and turn end down to about .220" and fit bushing same way. #3 rod for 30 cal, 338 and larger: use 17/64" rod and turn end to about .252" and fit bushings. The ends will drill and tap easily. Dave Kiff at Pacific Precision is making them now so those of you who don't want to make them can buy them and the bushings all from Dave.

I hold the range rod in the tailstock chuck as little as possible - only about 1/16" or so to allow the range rod to freely pivot back and forth as the bore moves. I've had better luck doing it this way than holding the rod more firmly in the chuck.

I did have an extra large bore and consequently a very loose fitting bushing one time and no tighter bushing, so for that particular job I bent the range rod slightly and held it firmly in the chuck so it would hold tighter against one side of the bore and I could get a pretty good reading on it, but it works way better to get a good fitting bushing and let it freely move.

One other thing to keep in mind is what Alinwa posted earlier - it's having more of the shaft outside the barrel to give more accurate readings (the pivot point is farther away from the indicator), so the longer the rod the closer your indicator readings will be to the actual bore movement you are measuring. I think 12" is minimum size and works really well, but it sure wouldn't hurt to go even longer yet.

After seeing how many questions guys had, even after seeing the Grizzly DVD, it really seemed to help quite a few guys understand so much better what was going on when they could see it in person and ask a lot of questions as the process went on. The DVD shows all the basics, but there are so many details that aren't on the DVD that I explained to people at the show in person, and it really seemed to help.

I do several classes a year now on long range shooting and after seeing the interest at the SHOT show, I think I will start offering classes in chambering, crowning and bore slugging/evaluation to interested people at my shop. I can do this about any time since I chamber barrels year-round. I have rifle ranges from 100 to 1000 yards right outside the door at my shop that you can also shoot on if you want, and my wife has started a bed & breakfast at our home for hunters and shooters if you need a place to stay (my shop is attached to my home and she's a great cook). Just let me know if anyone is interested.

Thanks!
Gordy Gritters

Joe Ponto
02-09-2008, 11:24 AM
Gordy it was a pleasure meeting you in person at the show. I wish I had more time to go over the technical points. One thing I have a difficult time with is the accuracy of the 12" (or longer) rod which has clearance in the pilot/bushing. I don't see how you can get proper readings with this inherent float/pivot.

Wouldn't a ground gage pin 12" long provide the best indicator for alignment?

Kurt Westfall
02-09-2008, 11:35 AM
Gordy. Don't know if you rembemer me, but we shot BR50 together when you ran the matches up there. I would be interested in the classes.

Gordy Gritters
02-09-2008, 12:22 PM
Hi, Kurt. I sure do remember you. I've often wondered if that was you when I'd see your name on a forum. We sure had fun back then, didn't we? Call me at my shop - 641-628-3044 - and we can set a date up for the class. (I only answer my phone from 2-5 pm, Central time, Monday to Friday, so call then if you can - or leave a message and I'll get back to you).

Joe, I sure enjoyed meeting you at the SHOT show also. It's always great to put a face to a name of someone I've only met on the phone or the internet.

I would think a close-fitting ground gauge rod 12" long would work great, but you'd have to have a great number of them to fit all the different size barrels in each bore size, which would be expensive. Bushings are inexpensive and work great!

Dialing it in initially with a range rod works extremely well for getting the bore running straight and true for purposes of cutting the shank and threads. But if you remember I drill out the hole for the chamber and then go in and get a direct reading off the lands ahead of the chamber with my long reach indicator to double check the range rod readings before I do the chamber. Sometimes I have to adjust it ever so slightly to bring it to as close to .0001" runout as I can get - it's almost always within a couple tenths or so - no problem at all for aligning and cutting the shank and threads.

Then I bore the drilled chamber hole so it's running true to the bore, and then ream the chamber, constantly checking for runout as I go. Done this way the chambers/throats always come out true and aligned to the bore like the ones I did at the SHOT show.

Thanks!
Gordy

ShelleyDavidson
02-10-2008, 07:55 AM
I watched your video and although I use different methods, I'd think I could be happy using yours, provided a 20" to 22" barrel could be done in my lathe using yours. I use a 16X40 Victor and have to utilize a dead center inside my spindle to catch the muzzle of the barrel.

My question: I use the Mitutoyo indicators and mine came with a .6"(approx) long indicator point. Your's seems to have a point that looks to be about 2" long. Doesn't that cause the resolution to be diluted? I chamber several point blank BR barrels per week and with the short cartridges, I don't need a longer point but if I did use a longer point, wouldn't .0001" runout on the dial mean that I actually had about .0003" in the barrel?

The specs on the big Grizzlys show normal runout at the spindle nose to be .0002". That's the same measured runout that my lathe has. And, sometimes I get chambers that show an honest .0001" so I know it's possible but, with the factory point on my Mitutoyo indicator, my .0002" capable machine usually produces .0002" work.

Shelley

Don
02-10-2008, 03:04 PM
Shelley

One thing I noticed while watching the video is that many times when Gordy is using the indicator with the long stylus he chokes up on the stylus point when running it against the rod. It looks to me like he turns that long stylus point into a short one (~the same length as the original short one) when dialing in with the rod. I assume he may do this because he then has the option of using a long stylus albeit a less accurate one when indicating up in the bore but more accurate on the rod without changing indicators.

My guess is that he does this only in the rough dial in portion of the process and it is so that the straight side of stylus can ride on the radius of the indicator rod without the ball point trying to track around the radius of the rod as it wobbles in the large rough dial in movements.

He than switches to the ball point end of the stylus for fine adjustments on the rod or barrel groove when trying adjust to .001 or less movement where the ball point radius of the stylus has little or no affect when riding a radius contour, where little change movement is involved..............Don

Gordy Gritters
02-11-2008, 08:57 AM
Shelley, depending on the size of the hole in your lathe spindle, it's not hard to make up a sleeve that slips over the end of your barrel a ways and either tapers to fit like a Morse taper or set screws in place. This makes the barrel long enough to reach out to the end of your spindle allowing it to dial in easily like a longer barrel.

My Mitotoyu indicators come with a .7" tip, and I use a 1.5" replacement tip available from MSC. This essentially halves the readings, so to measure .0001" I can easily "read between the lines" when measuring with the long tip, or "choke-up" on it 1/2 way up the stem like WSnyder says to get true .0001" readings. Works very well.

Remember I use the range rod to reach in much farther than the long tip will reach to initially dial the bore in as straight as possible for threading the shank and fitting the action. Then I pre-drill the chamber, which allows me to run the indicator in to give a direct reading off the bore itself to "fine-tune" the range rod readings, getting the bore to run even more true than the range rod can before boring the pre-drilled hole true and cutting the chamber. This gives very accurate and repeatable results.

Gordy

Stewart
02-11-2008, 09:11 AM
Gordy Halves? or doubles the read out? For example if it is reading .0001 now what will the indicator read with the longer probe?

Ralph

Gordy Gritters
02-11-2008, 10:07 AM
"Halves" - I guess it depends on how you look at it - sorry, Ill try to clarify this.

I mean the needle on the indicator dial will move 1/2 the amount with the long tip as it will with the short tip. So each .0001" graduation on the dial with a short tip is .0001", and each graduation on the dial with the long tip is about .0002". So to get a .0001" reading with the long tip, just go 1/2 way between each graduation if reading off the tip, or "choke-up" on the tip 1/2 way to give normal readings.

Hope this makes it more clear!

Gordy

Bnhpr
02-12-2008, 08:54 PM
Here's my range rod. 18" Drill rod is on order, but I'm trying brass first.

The length is 13" the tip is .220 the shaft is .235. Tapped 4-40.

Need to fit bushing and try tomorrow.

stockmaker
02-13-2008, 08:09 PM
I tried to get Shiraz's two helpers to shrink the mill and one of the lathes so it would fit in my RSR cart. Those darn guys would'nt do it unless I gave them a big pile of greenbacks........:D:D:D

tasy_ted
02-13-2008, 10:47 PM
the same results can be had with dave kiff range rods.

if you measure the amount the rod goes into the barrel then place ( 2 )
dial indicators on the rod one up close to the barrel and the other one
the distance that the pilot end is in the barrel tweak the cat end
to get both running at zero. you are doing the same thing as you do
when you are setting up in a action truing jig only on a bigger scale.
yes you are only truing a smaller amount of barrel but then you can do
as gordy does and go in with dial indicator and check after you have
drilled the chamber.??

regards tasy_ted:rolleyes:
still can spell ( range rod )

Rob Carnell
02-13-2008, 11:07 PM
The longer probe will (in my humble opinion anyway) tend to magnify the reading, so this should be even better than a shorter probe.

Rob Carnell
Sydney, Australia

JerrySharrett
02-14-2008, 06:05 AM
The longer probe will (in my humble opinion anyway) tend to magnify the reading, so this should be even better than a shorter probe.

Rob Carnell
Sydney, AustraliaRob, if the probe were 2 inches long and the tip traveled 0.002", then 1 inch down that probe toward the pivot, that 1 inch spot would be traveling 0.001", so, the longer the probe, the less is indicated on the dial for a given amount of measurement.

If that indicator were designed for a 1 inch long probe, then a 2 inch long probe would only move the dial half the amount that a 1 inch long probe would for a given amount of tip travel.

Did I make this sound confusing or do I need more coffee?

Bnhpr
02-14-2008, 08:50 AM
Rob, if the probe were 2 inches long and the tip traveled 0.002", then 1 inch down that probe toward the pivot, that 1 inch spot would be traveling 0.001", so, the longer the probe, the less is indicated on the dial for a given amount of measurement.

If that indicator were designed for a 1 inch long probe, then a 2 inch long probe would only move the dial half the amount that a 1 inch long probe would for a given amount of tip travel.

Did I make this sound confusing or do I need more coffee?

Clear to me Jerry,

What do you think about using a teeter totter? (I call them).

I have a Starrett one that is 2" on either side (4" total)

My test indicator has a short stylus. Or..Should I just buy a different indicator?

Ben

JerrySharrett
02-14-2008, 10:56 AM
Clear to me Jerry,

What do you think about using a teeter totter? (I call them).

I have a Starrett one that is 2" on either side (4" total)

My test indicator has a short stylus. Or..Should I just buy a different indicator?

Ben
I think you are talking about the probe bar that comes with a standard Starrett? Like the thingy in the middle of this picture?
http://cgi.ebay.com/STARRETT-196-DIAL-INDICATOR-SNUG-1-4-x-5-16-ACC_W0QQitemZ320217794399QQihZ011QQcategoryZ25272Q QssPageNameZWDVWQQrdZ1QQcmdZViewItem

If you are, that entire package is not as precise as I would recommend for barrel bore alignment.

What dial indicator do you have now?

Bnhpr
02-14-2008, 12:40 PM
I have an interapid test indicator, Starrett test indicator and Starret dial indicator/mag base.

The probe bar is the same as you show, but longer, I believe. (I'll get a pic) It's quite old but in good shape. I was just wondering if I could use it, with my interapid test indicator.

My thoughts were that the spring in the test indicator would keep the slop behind you in the probe bar.

Rolandr
02-14-2008, 06:13 PM
Can someone here send me an e-mail with Gordy Gritters contact info.

Thanks

Rob Carnell
02-14-2008, 07:13 PM
You are obviously correct, thanks for correcting my screwy logic!

Rob.

Gordy Gritters
02-17-2008, 07:25 AM
Rolandr, My contact info is as follows:

e-mail: gordy@wildbluepella.org

Phone: 641-628-3044 (I'm normally in my shop all day, but I'm very busy so I only answer the phone in the afternoons from 2-5 pm Central time, Mon-Fri)

Address: Gordy's Gunsmith Shop, 1648 Cordova Ave, Pella IA 50219

flatlander
02-17-2008, 09:27 AM
You can buy a longer stylus for the Interapid test indicator from MSC - no need to purchase another indicator. I bought a 2.75" stylus for my 312b-3 and a 2" stylus for a B&S bestest .0001" indicator (actually, the 2" B&S stylus was one of the two free contacts that they're giving when you purchase a bestest indicator from Enco). I've also got one of the Mitutoyo test indicators with the round body like Gordy uses in the DVD, but haven't purchased a longer contact point for it yet. Guess I should get cracking on that little detail, as it would fit into the rough-drilled chamber and allow me to check for bore runout before boring the drilled hole true.

Bnhpr
02-17-2008, 12:42 PM
You can buy a longer stylus for the Interapid test indicator from MSC - no need to purchase another indicator. I bought a 2.75" stylus for my 312b-3 and a 2" stylus for a B&S bestest .0001" indicator (actually, the 2" B&S stylus was one of the two free contacts that they're giving when you purchase a bestest indicator from Enco). I've also got one of the Mitutoyo test indicators with the round body like Gordy uses in the DVD, but haven't purchased a longer contact point for it yet. Guess I should get cracking on that little detail, as it would fit into the rough-drilled chamber and allow me to check for bore runout before boring the drilled hole true.

http://www1.mscdirect.com/CGI/NNSRIT?PMCTLG=00&PMAKA=06445357&partnerURL=http://catalogs.shoplocal.com/mscdirect/index.aspx%6Fpagename=shopmain%50circularid=11264% 50pagenumber=1341%50mode=


correct?

Bnhpr
02-17-2008, 03:48 PM
You can buy a longer stylus for the Interapid test indicator from MSC - no need to purchase another indicator. I bought a 2.75" stylus for my 312b-3 and a 2" stylus for a B&S bestest .0001" indicator (actually, the 2" B&S stylus was one of the two free contacts that they're giving when you purchase a bestest indicator from Enco). I've also got one of the Mitutoyo test indicators with the round body like Gordy uses in the DVD, but haven't purchased a longer contact point for it yet. Guess I should get cracking on that little detail, as it would fit into the rough-drilled chamber and allow me to check for bore runout before boring the drilled hole true.

Ok, I bought the 2.75" one. I also bought the drill rods from MSC, in case I do not like the brass ones.

Thanks eyeryone for the advice.

aleaddict
02-23-2008, 04:31 PM
Gordy --

I was one of the many "observers" at the SHOT Show demonstration, which was a very enjoyable experience. Just a suggestion for Grizzly, though…perhaps the company could double their floor space for next year, or at least request a "corner booth" so that more attendees of the SHOT Show can watch your excellent presentation. The overhead video display worked very well, but for us "curious 'smiths" it was very cozy experience.

-- ale

mike in co
02-23-2008, 06:23 PM
i'll jump in for grizzly...

there was NO room for grizzly this year, the space they got was the results of a cancelation...they made the best of what was available.
if you go back thru the posts you will see all of this........

mike in co

Shiraz Balolia
02-23-2008, 06:35 PM
I was one of the many "observers" at the SHOT Show demonstration, which was a very enjoyable experience. Just a suggestion for Grizzly, though…perhaps the company could double their floor space for next year, or at least request a "corner booth" so that more attendees of the SHOT Show can watch your excellent presentation. The overhead video display worked very well, but for us "curious 'smiths" it was very cozy experience.

-- ale

Actually, the only reason we got that booth was because they had a cancellation. It was 200 sq. feet, which is ridiculously small, but it was either that or nothing.
When we do shows, our normal booth size is several thousand sq feet. For example, we are doing the IWF in August this year (International Woodworking Fair - the largest woodworking machinery show in the world) and our booth size is 8,000 sq feet. We are taking about 100 different machines and will have 30 Grizzly employees there. SHOT Show on the other hand is very difficult to get space in and your choice of booth is based on seniority, same with most major shows. For the 2009 SHOT Show, we tried to get 1500 sq feet, but by the time it was our time to pick the largest space left was in the back of the hall, 400 sq feet. We took it and will just keep working our way up.

aleaddict
02-24-2008, 09:58 AM
if you go back thru the posts you will see all of this........

You're right. I meant to post my comment a couple weeks ago and just skipped over the last 3 or 4 pages.

Thanks again Gordy and Shiraz for the outstanding demonstration. My first knee mill was a Grizzly and it still runs great.

-- ale