Your method...

[wnroscoe]

How are you picking up the thread do you start small(diameter) and change your "Z" offset. What kind of machine are you using? I think more than one would like to know. Mark

Research verticle threading in a mill to include the tools required and you shall have your answer.

 

[Gundog 64]

Chad,
Ive got a question for you. Do you allow visitors in the shop? Im going to be in Lemmon for the pheasant opener, and my Dad and I usually make a trip down to the hills. I would love to talk to you about a project Im cooking up, maybe over a beer and burger. Let me know.

John Luitink

 

[NesikaChad]

I'd be delighted. Inxnay on the beer though, I wanna keep all my fingers out of the machines while they run.

2106 Lazelle Street, Sturgis, SD. 605.490.2561

Across the street from Pamida. Take exit 30, turn right, follow the "S" curve and I'm on the south side in a brand new cedar sided building about an 1/8 of a mile from the freeway exit.

Cheers,

C

 

[M.D.Spencer]

well

I'm sure it's a lot easier than doing a NPT thread. Mark

 

[MarkR]

Thank you guys so much!

For all of this useful info, and things to learn and think about. Chad, I think your method is out of my league for now, but it looks great.
Once again, thanks for all the info.
Mark

 

[Pete Wass]

Just a consideration

Knutz and boltz:

Unless an action has been used as a chock block for a commercial airliner or as a crowbar on an oil derrek chances are good the receiver bore is pretty straight. Since my ground tapered arbor fits tight it matters little to me because I datum everything off bore CL anyways. It can be out basically as much as it wants. I seriously don't care because when I'm done all my surfaces are going to be square, parallel, and concentric to it anyway.

As far as bolt slop goes. Yes in a perfect world it is/would be nice to have a minimal tolerance fit between the OD of the bolt and ID of the receiver bore. I have long advocated the almost zero tolerance/slip fit of a Nesika or Borden action just for this reason. (Borden bump feature is what I mean specifically)

In practice. Sit down with a trig cheat sheet or a CAD program and draw a tube with a .704" bore. Stuff a .695" OD stick through the center of it. Now load one side to the point of contact. You end up with .0045" of deflection from theoretical centerline. Now do the math.

A standard length Remington 700 bolt measures 4.400" from the lug surface to the front edge of the handle. When in battery with a loaded striker spring I have no doubt the cocking piece is pushing the bolt vertically as it tries to get over the trigger sear. It'll do this until the 12 o clock tangent of the bolt body contacts the 12 o clock tangent of the receiver bore. This means that only the lower locking lug is in contact with the receiver. That angle of deflection measures out to be .0586 degrees.

The half dozen Remington bolts I have floating around here all measure around .695" +/- .0015" so I'm feeling pretty good with my figures.

The "swept arc" of the locking lugs is around .980"

.980" - .695" ='s .290" Now divide that by 2. It's .145" that is the distance of the lug feature from the outside radius of the bolt body to the outside radius of the lugs. If you figure an angular deflection of that .0586 degrees referenced earlier in my little sermon you'll find that the "sloppy fit" between the receiver lug surface to the bolt lug surface is (drum roll please)


.00015" To put this in perspective gents, most high quality thimble micrometers are incapable of measuring this kind of dimension with any kind of reliable repeatability.

Now, it seems reasonable to me that when a 50,000 CUP cartridge lights its boiler room that .180955736847" square inches of cartridge rim (figured off a .480 cartridge case head OD) is going to have little issue with pushing that upper bolt lug the .00015" to square things up.

And all from a "chitty" pawn shop Remington 700.

My proof is you go to the firing lines of Camp Perry or any other Marquee NRA highpower match. There are dozens of Remmy 700's on the firing line and almost none of them have the little bushings epoxied on the bolt body that folks seem to rave about.

I realize benchrest guys are a very particular sort. Be that as it may I feel pretty good stating that the better shooters have realized long ago that 90% of a guns accuracy comes from a great barrel, careful ammunition preparation, and PRACTICE.

The other 10% is receiver, bedding, a crisp trigger, a good set of optics, and just dumb luck (meaning you beat the wind that day)

Hope this was at least entertaining if not even a little educational.

Cheers and all the best,

Chad


Chad Dixon
Gunmaker
LongRifles, Inc.

There is quite a difference between trying to get 10 shots inside a target the size of a trash can cover and hitting a tiny dot or trying to make one small hole in a target. It's the attention to the minutest detail that allows folks to hit tiny dots and make very small holes with multiple shots. Being cavalier about the small details is what seperates Gunsmiths from Hackers, IMHO.

It's unfortunate that the industry hasn't seen fit to get away from the angled trigger sear/ cocking piece to eliminat or minimize, a least, the bolt jacking up in the back but it hasn't yet. Change comes slowly to anal and cavalier folks sometimes.

 

[NesikaChad]

There is quite a difference between trying to get 10 shots inside a target the size of a trash can cover and hitting a tiny dot or trying to make one small hole in a target. It's the attention to the minutest detail that allows folks to hit tiny dots and make very small holes with multiple shots. Being cavalier about the small details is what seperates Gunsmiths from Hackers, IMHO.

It's unfortunate that the industry hasn't seen fit to get away from the angled trigger sear/ cocking piece to eliminate or minimize, a least, the bolt jacking up in the back but it hasn't yet. Change comes slowly to anal and cavalier folks sometimes.

Funny how a simple question derails into troll like comments. Even funnier when I remind myself that I use three $40-75K machine centers to do ALL my work and 99% of the industry uses manual machines that I am pretty sure have at least .00015" of runout. -And that's if they even have the instrumentation to measure it. Find me some Class 9 Gamut Tapered Spindle Bearings in a manual lathe.


Now if you don't mind, I have to go be cavalier, anal, and ignorant.


All the best,

Chad Dixon
Gunmaker (Hacker)
LongRifles, Inc.

 

[NesikaChad]

I'm sure it's a lot easier than doing a NPT thread. Mark

Actually a pipe thread isn't a big deal. Just annotate the taper in the parameter settings and the software does the work for you. the more challenging part comes with machining the taper in the mill. You can use the same process and just reduce the thread pitch value but you'll end up with this funky spiral surface finish. I've been working on revising my post processors (the working side of CAM software that actually coverts the fancy pictures on the monitor to the lines of code that tell the machine what to do) to have the ability to change my work planes so that it'll convert the short spline movements into actual G2/G3 arc movements automatically. This will be a great thing because it'll greatly reduce the thousands of lines of code that needs to be generated when working with NURB Splines. The second thing it does (and most important) is reduce wear/tear on the machines. A CNC drive servo is a powerful device that actuates the table surface to the correct position via the encoder. When you have these short spline movements (some less than .001) that servo gets the snot beat out of it because it's attempting to accelerate and decelerate to the programmed feedrate over that very short distance. The current/Amp load becomes quite high and they will eventually get burned up. A G2/G3 arc is linear and smooth. The machine understands it as it's part of it's basic programming structure.

Fun stuff.

I've experimented with a tapered thread on some home grown never finished receiver blanks, but the risk of chewing up soft, gummy threads kinda killed the experiment. If I ever get around to offering a receiver I intend to use a little different approach to support the barrel tennon. I'm looking towards a pair of malleable crush sleeves/rings and/or a collet type set up with a machined taper to load both ends of the tennon. The idea behind this is that it will mitigate some of the tensile displacement that takes place along the tennon/shoulder junction when a barrel gets pulled up snug. Harrold Vaugn rambled about the defalcations of a threaded joint in his book "Rifle Accuracy Facts" and it's always kind of had a bug in my ear ever since. I worked with a brilliant engineer from Seattle who makes a very good living designing fasteners for the aerospace industry. For what ever reason he took pity on my cavalier ways and educated me a bit on how threads really work. He wrote me an excellent reference paper that I still use for my machine shop side of the house. Pretty cool stuff.

I used to snicker at the Anschutz method of pinning a rim fire barrel to an action until after reading that book. It makes sense now.

Anyways. I better scoot.

Cheers,

Chad

 

[PEI Rob]

Question for you folks doing the bolt in the steady rest, dialed in with two test indicators and a jig to hold the head. Now, if I cut the rear of the bolt lugs true to the body, how can I possibly install a steady and not deflect the bolt body? Do you indicate as you install the steady? If I cut the face it will still be true to the rear of the lugs since it won't really deflect much given the short distance but it will be cut on a very slight angle. Is this so insignificant it isn't worth mentioning? Shouldn't we build a better jig so that the steady rest is installed before we start to true the bolt? Yes, I do as shown with the jig and recheck everything but still wonder if I should have made a better jig. Not a gunsmith or machinist, nor trained the least bit for it, just love to do the very best I can.

 

[Butch Lambert]

Chad,
I realize we are just metal munchers. I am getting tired of your attitude. You are not making friends and I have yet to see your name on an equipment list.
Butch

 

[NesikaChad]

Butch,

To be frank, I don't care if you like my attitude or not Mr. Lampert. I don't exist on this planet seeking your approval. If you will take the time to read this entire thread I have responded to the Op's and other's requests for information with detailed, accurate, and politely worded commentary and opinion. I have not touted myself as the greatest thing since sliced bread, I have not slung any insults towards anyone. All of my comments/opinions are based on mathematical fact that I verified with state of the art CAD/CAM software. I stand by everything I have said with ten years in this trade and several Olympic, World, and National event wins by very talented shooters in a variety of disciplines who took enough interest in what I do to allow me to either build or service their rifles. If that offends you then I guess we now know where each of us stand. I don't bash other gunmakers nor do I fill the internet with clouds of Disney land firearms fantasy. I tell black and white truth based on my personal experience and the input of mentors that have greatly aided my success in this business.

Thank you for your time and consideration. I consider this matter closed.

Last. Just what is an equipment list? I have no idea what that means.

Chad

Chad Dixon
Gunmaker
LongRifles, Inc.

 

[Butch Lambert]

Mr Dixon,
Your attitude is my peeve. I don't believe anybody questioned your vast knowledge of machining. I am not a gunsmith, but turn on a lathe and mill occasionally. I read your post as saying our machines are inaccurate and not capable of precision work.
By the way, How do you indicate your precision mandrell in your indexer. Do you have jack screws in it or do you shim it? !0 minutes to indicate it in?
Butch

 

[wnroscoe]

I tell black and white truth based on my personal experience and the input of mentors that have greatly aided my success in this business.

Me and you are of the same mind set. It makes it easy several weeks or years later to repeat the same thing and not have to worry if we're getting it right. I cant help but respect a man that has that stance in life.

 

[NesikaChad]

Mr Dixon,
Your attitude is my peeve. I don't believe anybody questioned your vast knowledge of machining. I am not a gunsmith, but turn on a lathe and mill occasionally. I read your post as saying our machines are inaccurate and not capable of precision work.
By the way, How do you indicate your precision mandrell in your indexer. Do you have jack screws in it or do you shim it? !0 minutes to indicate it in?
Butch

where's the attitude? Can your lathe indicate to .00015? Mine CANT and I'll tell that right up front. Neither can my mill so what is the point your trying to make? I don't have attitude. Take your ego off three round burst for a minute and read the damn post again.

 

[Dennis Sorensen]

I kind of got the same impression as Butch... I thought the comment, "Funny how a simple question derails into troll like comments." showed a little attitude. ... I didn't interpret any troll like comments in the post that enticed that response... The next one, "Take your ego off three round burst for a minute and read the damn post again. " definitely does and post 31 too ... but that is just my perception...

 

[Zebra13]

Did the post wherein Chad is inferred to be "cavalier" about the little details and a "hacker" not come off as a touch abrasive? I bet that if that shot had been fired across your bow, you would be a trifle annoyed. And your response similar. What kind of "attitude" would you have adopted?

And his "attitude" is so bad that a few posts later, he invites another member to come down and hang out at his shop, complete with directions. He sounds like a real prick to me.

Gimme a break...

Your "attitude" is fine, Chad. I get what your saying.

Justin

 

[Wayne Shaw]

Aside from the attitudes....

Having a bunch of high dollar machines is great, and no doubt produces great results. However......

Messing with a Remington, in my humble opinion, should only go so far. To coin a phrase from last year, "you can put lipstick on a pig, but you still have a pig".

Remingtons are great, they shoot great, and a whole industry has been built to support them. But the attempt to make a production Remington perform equal to a custom action is throwing good money after bad.

Don't get me wrong, some things can be done that help out a bunch, over and above the way they come. Facing the action true on a mandrel, running one of the piloted thread taps in to ensure the threads are in line, facing the lugs both bolt and action, is about all that generally is needed. And that is probably more than will ever be realized on paper.

I do believe if you want a slick working action, some timing needs to be addressed, but that is icing on the cake.

The clones that are available now, for a great price, just make dumping the effort into the retrofit somewhat a bad choice.

The normal work on Remingtons can be done very well on machines and equipment that don't require you to pull a second mortgage on your house.

 

[Dennis Sorensen]

cav·a·lier (kv-lîr)
n.
1. A gallant or chivalrous man, especially one serving as escort to a woman of high social position; a gentleman.
2. A mounted soldier; a knight.
3. Cavalier A supporter of Charles I of England in his struggles against Parliament. Also called Royalist.
adj.
1. Showing arrogant or offhand disregard; dismissive: a cavalier attitude toward the suffering of others.
2. Carefree and nonchalant; jaunty.
3. Cavalier Of or relating to a group of 17th-century English poets associated with the court of Charles I.

It isn't such a bad word...

Lets let this rest and find other things to discuss rather than slog at each other...

For instance:
Has anyone done a scientific test about the rear bolt slop (up to 10 thou clearance) and the effect it has or has not on accuracy? Does "bumping" the rear of a 700 bolt give better accuracy than one that has 5 thou clearance? I know it feels nicer... What kind of a test would be required? Would it ever be conclusive?

.

 

[Boyd Allen]

Awe come on fellas...don't stop now. It was just getting interesting.

Seriously, posts have the disadvantage of lacking facial expression. Without this clue, sometimes it is easy to get riled unnecessarily.

One more thing...thanks to this thread, I have gone from guessing that thread milling must involve making threads on a milling machine, to a better understanding of the basics of how this is accomplished. Thanks
Boyd

 

[Butch Lambert]

Chad,
All this aside, can you tell me how you indicate your mandrell while it is in the indexer?
Butch