Dialing in your bbl

Fitch, I use copper as it deforms and grips the barrel better. I have used 2 spiders from the get go as I had to because of a long headstock. I have never had a slip.
I guess that I need a longer rod to try to slip one all the way through. I have had a couple that got a little hard before 12" of the rod was pushed through. I did not force it.
I'm not as worried about the muzzle as much as the chamber being coaxial to the lathe bearings. I have a long reach Interapid, but have gone to the Mitutoyo 312 type indicator with the short stylus as Jackie uses. The long stylus just jumps to much for my comfort going from lands to grooves and you don't get a true .0001 reading.
Butch
 
Mr. Butch from the time you slide the bbl thru the headstock and indicate it in, about how long does that take you on average? I'm figuring probably take me twice to 3 times as what you experienced guys do.

When you get .0001 on the chamber end what kind of reading do you have on the muzzle end? thanks joe
 
Joe,

,
You asked for it and here goes. I do not claim that there are not better ways out there and I like Rusty Stud have altered out methods through the years. A new rookie with just a little lathe experience can do this in 4hrs or less. I have done several and it takes 2-2 1/2hrs.
I chamber in the headstock as it allows me to do all the chamber work without moving the barrel and it is done in one setup. As stated before, I have 2 catheads and all the screws in both have 1/4" copper inserts. It gives grip and allows the barrel to pivot when indicating. I have a set of Deltronic pins for each caliber that I chamber. That is 7 sets of 25 pins ea. They come in .0001 increments. For example Shilen targets .237 as their mean bore dimension for 6mm and you can get the same from Bartlein and Kreiger. My middle pin is .237. I have 12 pins below that number and 12 above. It gives me a range of .2358-.2382. After cutting about 1 1/2" of the breech end and initially 1" off the muzzle end I set it up in the lathe. The breech and muzzle will be a little sloppy from the lapping and that is the reason for cutting some off both ends. I indicate a slip fit pin on either end until a .0001 indicator doesn't move. I drill the bore with a drill that is approx. .060 under the diameter of the shoulder of the cartridge. At this time I can put my 513-504 Mitutoyo .0001 indicator into the drilled hole and then I indicate the grooves to .0001 and check the heights of the lands at the same time. If the land heights vary .0002 or so the barrel goes back. I am indicating the throat, the first thing the bullet sees. I cut the tenon to diameter to size and length. I thread and check with my thread mike. I have both carbide and tool steel thread cutting tools. I personally prefer tool steel. With my tenon turned and threaded I turn my attention to chambering reaming. I initially put my reamer in the tailstock and indicate my compound to the exact same angle as the body of the reamer. I use a short stiff carbide boring tool and taper bore in the compound to within .010-.020 of the shoulder diameter and .100" short of finished length. I do not use a chuck or floating reamer holder any longer. I made a reamer holder that slips over the reamer and has a point on the back with a .030 radius on it. It has a handle that screws into the side of it and it clears my ways. I made a pusher to fit in the chuck. Just a piece of stainless with a 1/2" shank and a 1" flat face. The flat face bears on the radius of the reamer holder and allows it to float if needed.
Crowning is the same basically, just turn the barrel around and repeat. I do both my hunting rifles and benchrest rifles the same way. Are we anal in our setup, probably, but we feel better when we are done.
Before you take your setup apart, run your tenth indicator back into the throat and check your setup after all of your machining is done. If you did a good job your indicator will tell you.
This is 2 finger typing and I am tired. Comments are welcome. I am going to bed.
Butch
 
It is "putting"

There is no proof in “pudding”, although it can be very tasty.:D The proof is in the “putting”, as in putting the procedure or product to the test. Somewhere, somehow, somebody thought that if the pudding didn’t set (get thick) that was some kind of proof.:confused: Well it is, because “Pudding” is made with corn starch or eggs and if you end up with a mess then something is wrong, duh!:eek: However we are not concerned at this time with culinary skills but “Best Machining Practices” therefore I suggest that we start “putting” these to the test and leave the "pudding" for desert!

I like Chocolate,:)
Nic.
 
"Word Detective and other etymology sites pointed out that the phrase originated as "the proof of the pudding is in the eating." It means that the true value or quality of something can only be judged when it's put to use. The meaning is often summed up as "results are what count."

According to Bartlett's Familiar Quotations, the phrase dates back to at least 1615 when Miguel de Cervantes published Don Quixote. In this comic novel, the phrase is stated as, "The proof of the pudding is the eating." ........:D
 
As to the Two line vs. One line method, remember, all the steadyrest chambered barrels are One liners. It's just that the two points that define that line, one of them is at the base of the chamber not at the chamber neck.

There is a variation of the above that really helps. Some steadyrest chamberers, especially the benchrest chamberers, use an adjustable bushing that allows a better alignment of the chamber end.

Chamberers?? Is that a word? Either that or barrel fitters.

Consider one more thing in this discussion. If you have ever seen a gun drill operation, you will immediately realize the gun drill can not suddenly move out of cylindricity. It would bind and break. We have drilled 1/8" diameter holes 24" deep in SAE 4140. One thing that helped we were rotating the part and the gun drill.

(Yes, cylindricity is a word.-look up GD&T standards from the metrification efforts of the '80's)
 
Butch Lambert said:
Fitch, I use copper as it deforms and grips the barrel better. I have used 2 spiders from the get go as I had to because of a long headstock. I have never had a slip.
Click to expand...

Thanks for the input - I'll get some heavy copper wire and make up a second set of spider bolts.

I guess that I need a longer rod to try to slip one all the way through. I have had a couple that got a little hard before 12" of the rod was pushed through. I did not force it.
I'm not as worried about the muzzle as much as the chamber being coaxial to the lathe bearings. I have a long reach Interapid, but have gone to the Mitutoyo 312 type indicator with the short stylus as Jackie uses. The long stylus just jumps to much for my comfort going from lands to grooves and you don't get a true .0001 reading.
Butch
Click to expand...

I've been playing with my DTI in the muzzle of the barrel a fellow shooter loaned me. I'm not having a lot of luck with it. My project for today is to experiment to see if using a slightly bent piece of 3/16" brass rod held in the tail stock chuck so it forces itself against the side of the bore works better. I could make a slightly smaller than bore diameter brass tip for it and try that too. Sort of a poor man's version of a Grizzly rod.

This might be interesting.

Fitch
 
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Fitch,
Go to your electrical supply house or Home Depot and get some small diameter copper grounding rod. It is a little harder than copper used for electrical wiring I believe.
Butch
 
Butch,

The 308 bbl I chambered the other day, I wanted to use my new mitutoyo indicator in the bored hole.

I had everything completed and ran the indicator body into the chamber. My problem was that the stylus did not touch the lands. It was plenty long, but the bored hole was not big enough to adjust up and down enough to touch the lands.

My question is, should I remove and bend the stylus?

Ben
 
Bnhpr said:
My problem was that the stylus did not touch the lands. It was plenty long, but the bored hole was not big enough to adjust up and down enough to touch the lands.

My question is, should I remove and bend the stylus?

Ben
Click to expand...

The stylus is just a friction fit in the end of the indicator. It can be moved up or down and within limits to any angle you desire. Just grab it and move it to the angle you want. It won't break. Really it won't.
 
A must read for the new guy on chambering!

frwillia said:
Joe,

I've done what Butch suggests. I spent hours doing searches on this and two other forums, pasted what I considered to be the best parts of related threads (some of the best parts were dialogues on various ways to do things) into an MS-WORD document. I can print it as a PDF file and e-mail it to you. It has a ton of useful data in it. A lot of the posts came with pictures. I printed it, put it in a loose leaf notebook and studied it.

Fitch
Click to expand...

Mr Fitch e-mailed me the .pdf file he has put together on chambering. It is a must read for the new guy and maybe the experienced may enjoy the read.

It is 131 pages Fitch has put together from all over the web. I have searched chambering on and off for a couple of months and have not found half this info. It has plenty of pictures, has an extensive section on barrel removable and required vises. plenty of other "stuff" that pretains to barrels and accuracy chambering.

Fitch has combined what would take most of a year to find in a .pdf file. The "FITCH REPORT" would be a must read on chambering if you have any questions.

Shoot fitch and e-mail i i bet he would send it to you! You will appreciate his effort in combing everything in a place.
thanks Fitch!
joe
 
Thanks Joe.

I have a spam filter that's about as friendly as a mugger in a dark alley, but Joe and a couple of others have followed the instructions and gotten through.

Fitch
 
Hey Fitch,
If you have a pretty good composition of that PDF file consider putting it on the benchrest.com blog page. It would be help to a lot of new chamberers.
 
frwillia,

I have been reading on chambering barrels for almost a year and have chambered my first one recently.
Would love to see what you have come up with if you would like to share.

tim@bigfootsigns.net

Thanks,

Signguy
 
Butch Lambert said:
Ben,
Mr. Snyder is saying the same thing that I told you in the PM. Maybe his terminology is a little better.
Butch
Click to expand...

I didn't get the pm yet, but I'm glad it is something simple.

I didn't want to break it.

Thanks Snyder and Butch.

I'll try it again soon. I have 6 bbls to put on in the next few months.

Ben
 
Signguy said:
frwillia,

I have been reading on chambering barrels for almost a year and have chambered my first one recently.
Would love to see what you have come up with if you would like to share.

tim@bigfootsigns.net

Thanks,

Signguy
Click to expand...

I'll check my log book, but I have 23 bbls chambered so far, based on the expertise of folks here.

Every one of them shoots hole on hole with good loads. Only one has gone back in the lathe to do so, but...I'm yet to scrap a barrel.

If you follow the basic procedure of chambering through the headstock, and direct indicating the throat area, with good barrels and tooling, you will be successful.

Apparently some people are successful with the range rod/gritters technique, but I was not comfortable with it, and it was not repeatable for me.

Before you cut the chamber, try repeating the indication, and see if your results are the same. That's my only 2 cents of advice.

Ben
 
Stay after it Ben,
Fitch, here is a photo of my set screws that Gene Bukys was kind enough to do for me.
DSC01699-2.jpg

They work very well and if they ever wear out, I can replace the tips.
Butch
 
Butch Lambert said:
Stay after it Ben,
Fitch, here is a photo of my set screws that Gene Bukys was kind enough to do for me.

They work very well and if they ever wear out, I can replace the tips.
Butch
Click to expand...

They look really good. I will get some copper tomorrow. Ought to be a piece of cake to make them.

Thanks

Fitch
 
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