To clear up some misunderstand on bore size

Butch Lambert · Apr 8, 2017

The parts and production feller is trying to button rifle a barrel. He has been pushing back on some of my info. I just received two emails from 2 friends that are in the business, but with different companies.

That size is exactly what varies from one heat of steel to another heat. In generalities the size before buttoning on a .308 will be around .2992 - .3008. After stress relieving and lapping .0002-.0003 out we want to end up at .3000".

The other:
Bore should be around .2995 or slightly bigger before lapping. Try to be right at or around .3000 lapped.

These guys have been in the barrel business for a lot of years with a couple of the best known barrelmakers. I have emails out to a couple more barrelmakers that I know. I will share what they say to me.

Parts and product guy, I will share what I know and what I can find out for you. I don't have a clue why you are pushing back on this.

JohnMc45 · Apr 8, 2017

Good to know the information I had collected was leading me the right way. The only thing I can think of is that maybe he is trying to rifle small diameter blanks and the whole blank is expanding leaving him with shallow rifling. Leading him to think he needs to make the bore smaller.

Butch Lambert · Apr 8, 2017

JohnMc45 said:
Good to know the information I had collected was leading me the right way. The only thing I can think of is that maybe he is trying to rifle small diameter blanks and the whole blank is expanding leaving him with shallow rifling. Leading him to think he needs to make the bore smaller.

John, even on the 1.500 unlimited blanks you can feel the button as it travels in the bore. If you check them with say Deltronic pins you will find the bore hasn't changed. He may want to check out Danjon-http://www.danjon.com/ Lots of rifling tooling.

JohnMc45 · Apr 8, 2017

Butch Lambert said:
John, even on the 1.500 unlimited blanks you can feel the button as it travels in the bore. If you check them with say Deltronic pins you will find the bore hasn't changed. He may want to check out Danjon-http://www.danjon.com/ Lots of rifling tooling.

That's what I mean. If you can feel it in a 1.500 x.308 blank with about a 0.600 wall
Think what would happen if he was trying like 0.625-0.750 x .355 that's only a wall of 0.135-0.197
The steel maybe stretching over the button leaving very minimal rifling. His conclusion is his hole is to big not that his blank is to small in diameter. Try's again with smaller bore and gets better results therefore proving to himself that he was right. But the better results are not from the need for a smaller hole but the need for a higher pressures to fully form the rifling.

Butch Lambert · Apr 8, 2017

JohnMc45 said:
That's what I mean. If you can feel it in a 1.500 x.308 blank with about a 0.600 wall
Think what would happen if he was trying like 0.625-0.750 x .355 that's only a wall of 0.135-0.197
The steel maybe stretching over the button leaving very minimal rifling. His conclusion is his hole is to big not that his blank is to small in diameter. Try's again with smaller bore and gets better results therefore proving to himself that he was right. But the better results are not from the need for a smaller hole but the need for a higher pressures to fully form the rifling.

John, that ain't true. Barrels are some times rifled after contour. If it doesn't work for him, either his tooling is not correct or his lube. Lube is a close held secret.

Butch Lambert · Apr 10, 2017

From another major barrel maker.

Hey Butch! Proper min spec. bore size is .3000" +.0005".

Most button barrels (even custom ones that's why they offer different grades of barrels) and especially factory barrels run big. I just checked a FN Patrol rifle in .308win. for the local cops. The bore size was almost .301". Actually came in at .3009" and the grooves we're at .3090".

Later, Frank

dbsuthe · Apr 10, 2017

I could be wrong, but this is my understanding;

The specs for that chamber and bore are easy to get from SAAMI. Just download http://saami.org/specifications_and...s/download/Z299-4_ANSI-SAAMI_CFR.pdf#page=110 and go to page 110. The top part specifies the bullet, the bottom has the chamber and bore. Then look at page 306, where it gives the tolerance; the finished bore is .308 to .3085

I would expect the button to work like thread forming, with the metal upset (pushed away) from the grooves and filling in the area that makes up the bore. So it makes sense that you would drill to between .2992 and .3008, depending on the button. If you start at .2992 and move the metal from 4 grooves of .176 wide and .004 deep to the areas between the grooves, the bore will become smaller and thus the .002 or .003 to ream out.

Butch Lambert · Apr 11, 2017

dbsuthe said:
I could be wrong, but this is my understanding;

The specs for that chamber and bore are easy to get from SAAMI. Just download http://saami.org/specifications_and...s/download/Z299-4_ANSI-SAAMI_CFR.pdf#page=110 and go to page 110. The top part specifies the bullet, the bottom has the chamber and bore. Then look at page 306, where it gives the tolerance; the finished bore is .308 to .3085

I would expect the button to work like thread forming, with the metal upset (pushed away) from the grooves and filling in the area that makes up the bore. So it makes sense that you would drill to between .2992 and .3008, depending on the button. If you start at .2992 and move the metal from 4 grooves of .176 wide and .004 deep to the areas between the grooves, the bore will become smaller and thus the .002 or .003 to ream out.

Yes,you could be wrong. I didn't look at your attachment, but you are quoting groove diameter not bore diameter. They are not reamed after being rifled. I believe that a slight lap of about .0002" after the blank is rifled is the final operation on the ID.
I might add that the quotes that I posted came from the largest, and 3 of the most successful custom barrelmakers today. These 3 guys did not learn barrel making by reading a book.

partsproduction · Apr 12, 2017

Butch, why not just talk to me instead of about me?

I wasn't trying to push anyone, whatever that is. I assumed you were thinking of cut or broached barrels, they would indeed need to start with the minor diameter.

The information I got from the button seller for a .356" finished rifled .380 ACP bore is to start with .348", well, .348" gave me unfinished lands. When I tried smaller bores in blanks I got much better rifled bores.
I found my best barrel so far;

An attempt to photograph the riflings didn't work;

But here are two slugs, the short one from a KelTec barrel and the longer one from mine;

Which ever slug is farther from the light shows the riflings best. Note that my twist rate is faster;

Looking down my barrel and that of the KelTec I see very little difference, measuring both I find perhaps .001" maximum difference between them. In both cases the lands are .0025-.0028" high, quite low compared to your .308 barrel specs, which I suppose would be expected.
My blanks have had 1 1/4-12 threads at one end, but since that is the end with the button chamber the extra girth didn't effect anything. I hope to either start with 1" 416 stainless and turn them after rifling or make a sleeve to contain the bulging so rifling lands can rise from the median bore. As pointed out, thread forming starts from the median diameter, the thread tops rising through that from displaced metal.

Though I'm not done by any means I've come to the conclusion that any mechanically minded person with a few tools could easily make reasonable quality barrels for his own use, which is, of course, legal to do.

Whatever push means please forgive me as it sounds argumentative, I don't know what anyone else does, I was only looking for a source for documentation available to anyone, but apparently it's not.

My best barrel is far better than the worst commercial barrels I've found on some of my own guns, in fact I'd be ashamed to sell a new gun (If I were in that business) with one .22 barrel that came on a small revolver I bought new.
Lest that sounds boastful please remember you haven't seen that .22 barrel, and my own shop made barrel is far from as nice as most commercial barrels I have. However, one lesson for sure is that high quality barrels can be made in any machine shop. That does not mean they can be made economically of course.
Recently a thread in PM "general" brought up the very high quality of hobby machining examples shown in some model engine shows, and I've often thought the same thing, that the skill rises at least to the level of commercial production shops, and also, that a guy in a home shop may take ten times as long to do it too, so it's not comparable.

I don't know where the anger comes from as I never said I was going to try to compete with barrel makers commercially. I just wanted the title of any books or papers that expound on button riflings barrels, that's all.

Butch Lambert · Apr 13, 2017

Parts guy, I'm certainly not angry, I'm amused. I guess I don't understand a person that asks for info and given it from the best barrel makers in the World, resists their knowledge. So your Chinese button maker is the end all?
Have you looked at Danjon's site yet?
If you continue with your present thinking and disregard the advice from reputable barrel makers, guess what?

JNieman · Apr 13, 2017

Nothing personally against Kel-Tec...

...but they are nowhere near the top of the list of whom I would gauge quality barrels from. You need better standards if you're going to debate barrel making.

partsproduction · Apr 13, 2017

First, Butch, go ahead and be amused, be condescending, I don't care. You weren't here when I did my experiments, all you can do is speculate without seeing why I came to my questions about firm documented data.

I told you blanks with bores close to finished size do NOT form finished riflings with the carbide buttons I have, what others do does not seem to have any effect on what I see with my own eyes.

I do appreciate information from others, though I keep thinking you may be confusing cut and broached barrel making with button rifling. If someone else can get good riflings from near finish sized bores I'm interested, but I haven't had that experience myself with the buttons I have.

BTW, where did you get the "Chinese button maker" notion? I said they were made in Germany. What is that about Butch? Huh? Trying to diminish someone who simply has a difference of opinion? You should look inside yourself at your motivations. Why does it seem to bother you that a guy can make his own barrels? That's what I don't get. I will say that making light of the other guys efforts is certainly easier than bettering them, it's been hard work.

Butch, try it yourself, you might find it is fun, and I won't try to make fun of you.

JNieman, I've said several times that I'm not trying to make target class barrels. Plus I've also said that my early prototype barrels are better than some commercial American gun makers barrels. I grant that every gun maker has bad products that get past QC, and that's doubtless what I see in those cases.

I have implied several times now that I wasn't trying to make a Korphilia. I'm not selling my barrels, not bragging about the quality either, simply saying that anyone with a machine shop and the desire to do it can make effective pistol barrels, and probably rifle barrels too by pull button rifling. I'd like to see people begin in large numbers to try it, it is very gratifying when you look down your own rifled barrel.

There are youtube videos of people making cut rifling machines, and combination gun drilling/reaming and rifling machines, in their basements, high quality rifle barrel capable machines, not high production but that's not the point.

And Also, there really is no reason why, passing the experimentation phase, very high quality barrels could not result, in fact my experiences have been that excellence comes through continuous effort.

Eventually I'd like to explore the methods to effectively make small batches of non corrosive primers as well, and document the process.
Two or three one or even 1/2ton OBI presses should do the trick.

My point is that the American people will always enjoy our constitutional rights. Every aspect of how to insure that power mad politicians can never take the RTKBA away should be exploited on a large scale by every freedom loving American, political efforts, teaching young people to shoot safely, joining the NRA and other groups, and home gunsmithing to name a few.

If you go on youtube you will see many shop made non commercial handguns, from crappy looking jokes to very high quality ones. I can't think of a better way to spend free time, or get more gratification from it. Even the sick looking home made guns are part of the exercise of the RTKBA, and much more so if they are reliable.
Look at "Nonesuch" in youtube who makes crude looking guns and Serbu who makes nice ones and has worked with Nonesuch. Serbu has a manufacturing license but much that he is doing could be done by anyone with a mechanical aptitude. Who knows? I may get a manufacturers license myself some day. We are only limited by our own attitudes.
partsproduction

cabf12 · Apr 13, 2017

Hello all,

This is quite interesting topic as the question whether actually the metal is displaced from grooves into lands during buttoning.

To my experience, it definitely doesnt happen at wall thicknesses less than 1/4 inch.

Parts Guy, are you talking about that rifling button?
Rifling button - 38 ACP | eBay

If yes, can you measure its middle and tail diameters, with a micrometer, preferably, or good caliper? I am wondering how much playoff does it have or whether the tail is ironing the lands too much.

Butch Lambert · Apr 13, 2017

partsproduction said:
First, Butch, go ahead and be amused, be condescending, I don't care. You weren't here when I did my experiments, all you can do is speculate without seeing why I came to my questions about firm documented data.

I told you blanks with bores close to finished size do NOT form finished riflings with the carbide buttons I have, what others do does not seem to have any effect on what I see with my own eyes.

I do appreciate information from others, though I keep thinking you may be confusing cut and broached barrel making with button rifling. If someone else can get good riflings from near finish sized bores I'm interested, but I haven't had that experience myself with the buttons I have.

BTW, where did you get the "Chinese button maker" notion? I said they were made in Germany. What is that about Butch? Huh? Trying to diminish someone who simply has a difference of opinion? You should look inside yourself at your motivations. Why does it seem to bother you that a guy can make his own barrels? That's what I don't get. I will say that making light of the other guys efforts is certainly easier than bettering them, it's been hard work.

Butch, try it yourself, you might find it is fun, and I won't try to make fun of you.

JNieman, I've said several times that I'm not trying to make target class barrels. Plus I've also said that my early prototype barrels are better than some commercial American gun makers barrels. I grant that every gun maker has bad products that get past QC, and that's doubtless what I see in those cases.

I have implied several times now that I wasn't trying to make a Korphilia. I'm not selling my barrels, not bragging about the quality either, simply saying that anyone with a machine shop and the desire to do it can make effective pistol barrels, and probably rifle barrels too by pull button rifling. I'd like to see people begin in large numbers to try it, it is very gratifying when you look down your own rifled barrel.

There are youtube videos of people making cut rifling machines, and combination gun drilling/reaming and rifling machines, in their basements, high quality rifle barrel capable machines, not high production but that's not the point.

And Also, there really is no reason why, passing the experimentation phase, very high quality barrels could not result, in fact my experiences have been that excellence comes through continuous effort.

Eventually I'd like to explore the methods to effectively make small batches of non corrosive primers as well, and document the process.
Two or three one or even 1/2ton OBI presses should do the trick.

My point is that the American people will always enjoy our constitutional rights. Every aspect of how to insure that power mad politicians can never take the RTKBA away should be exploited on a large scale by every freedom loving American, political efforts, teaching young people to shoot safely, joining the NRA and other groups, and home gunsmithing to name a few.

If you go on youtube you will see many shop made non commercial handguns, from crappy looking jokes to very high quality ones. I can't think of a better way to spend free time, or get more gratification from it. Even the sick looking home made guns are part of the exercise of the RTKBA, and much more so if they are reliable.
Look at "Nonesuch" in youtube who makes crude looking guns and Serbu who makes nice ones and has worked with Nonesuch. Serbu has a manufacturing license but much that he is doing could be done by anyone with a mechanical aptitude. Who knows? I may get a manufacturers license myself some day. We are only limited by our own attitudes.
partsproduction

Mr parts person,
You are judging me because you do not like what I am posting. If the top barrel makers say something and you disagree, It leads me to believe you are short of something or quite a few things.
Why don't you post when you are up and running with your ideas of making rifled barrels. I doubt that I live that long.

partsproduction · Apr 13, 2017

I doubt that I live that long.

See how you are Butch? You have to see it for yourself before you can change. I feel a little sorry for you.
And the user name is "partsproduction", not "Mr. parts person", what is that Butch? Please think about it. No one responds positively to personal denigration's. It doesn't hurt me, but it bothers me a little that you can't see it.

traditional-tools · Apr 13, 2017

partsproduction said:
See how you are Butch? You have to see it for yourself before you can change. I feel a little sorry for you.
And the user name is "partsproduction", not "Mr. parts person", what is that Butch? Please think about it. No one responds positively to personal denigration's. It doesn't hurt me, but it bothers me a little that you can't see it.

What does any of that have to do with this thread ? :confused:

partsproduction · Apr 13, 2017

What does any of that have to do with this thread ?

Really? How can a conversation take place when there is the sort of ridicule apparent in these two threads? Is not the point of a forum to exchange information? Given these two facts you may want to think it over again.

Here;

The parts and production feller is trying to button rifle a barrel. He has been pushing back on some of my info.

Wrong and disingenuous, my user name is not "The parts and production feller", (that is the kind of thing that angers people) and "He has been pushing back on some of my info" is wrong again, I was discussing a difference between what he was saying and what my findings had been, which made me think he was confusing cut or broach rifling with button rifling, which is a forming process. And I'm not trying to button rifle a barrel, I've already made 1 good barrel and 2 others good enough.
I've gone way overboard trying to explain to him that I never claimed to be making top quality barrels yet, if he has production experience he should know that quality comes up with experience over time.

"To clear up some misunderstand" I don't know what that means.

In that sense possibly the thread title is in error, there is no lack of understanding on my part, perhaps on his. I know this much for a fact, if Butch was trying to convince me (As if he had to!) that I was wrong in my conclusions he could have said so in a friendly way.

Is it possible that some other barrel makers start at minor diameter? Sure, why not. How am I "Pushing back" by saying that my limited experience has shown me that my expensive GERMAN made buttons (That was another rotten dig, "Chinese made buttons".) may like a smaller pre button bore? Does reality change because someone else uses different buttons?

Is it at all even remotely possible that buttons made by a different company might need a smaller starting diameter?

Did I say anyone was lying? Did I even say anyone was wrong? I questioned whether or not he was quoting from the same process, but I wasn't trying to say anything bad about him, at least not on that account.
It's hard to communicate with people when they constantly talk down to you, and you might feel the same if it were you.
I've been involved in internet conversations since the 1990's, and I know people read things into what others say that aren't there. But I also know when someone is deliberately trying to put me down.

A real good example is

I doubt that I live that long.

I've already been successful in making a good barrel blank, so his "doubt" is misplaced.

I want to say here and now that I wish Butch the best and a long life. His ideas of how to make friends may need some work.

partsproduction

72bwhite · Apr 14, 2017

just what we need another jackass haranguing
one of the people who actually knows stuff

like that bozo and spearchucker

barrel making is loaded with tribal knowledge
getting told what the starting bore size is a leg up.

a cut rifled barrel is reasonably easy once you get the drilling and reaming part down.

partsproduction · Apr 14, 2017

a cut rifled barrel is reasonably easy once you get the drilling and reaming part down.

But of course no one was really talking about cut rifled barrels were they? Maybe the jackass isn't who you imagined it to be anymore than cut rifling was being spoken of here.

oliver88 · Apr 14, 2017

I manufacture button rifle barrels and I can tell you that you are not going to find any specific button sizes from a book.
That is the black magic stuff that we all learn the hard way. It has to be tweaked and adjusted specifically for our machines and operation.

I admire you for trying this and these guys were giving you some solid information.
Just keep chipping away and you will get it the way you want it.

To clear up some misunderstand on bore size

Titanium

Plastic

Titanium

Plastic

Titanium

Titanium

Hot Rolled

Titanium

Titanium

Titanium

Titanium

Titanium

Plastic

Titanium

Titanium

Diamond

Titanium

Titanium

Titanium

Plastic

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