Posted 22 October 2010 23:18 Hide Post

quote:
Originally posted by jeffeosso:

quote:
Originally posted by bartsche:
forget the reboreing it usually is a no go with cold formed barrels, roger



ah, just what, exactly, do you mean by colf formed barrels? all button and cut rifles are "cold" .. and you most certainly can rebore and recut ... as, frankly, that's how they MAKE them .. bore a hole, cut the rifling ...



shockerPerhaps someone who is into reboring can help you understand as they did me on Mauser cold formed barrels. Any volunteers? homerroger


From another forum.

go hit "quote" on your other post, Roger, and bring the formatting over ...


here, i'll do it for you

quote:

Originally posted by bartsche:

quote:

Originally posted by jeffeosso:

quote:

Originally posted by bartsche:
forget the reboreing it usually is a no go with cold formed barrels, roger

ah, just what, exactly, do you mean by colf formed barrels? all button and cut rifles are "cold" .. and you most certainly can rebore and recut ... as, frankly, that's how they MAKE them .. bore a hole, cut the rifling ...

Perhaps someone who is into reboring can help you understand as they did me on Mauser cold formed barrels. Any volunteers? roger

I am waiting for the answer, btw ..

but, since it's your story .. why don't you tell us YOUR understanding of it, as you posted the "warning" ..
Let's see .. do you mean cut rifle? that's cold .. how about button? that's cold .. Hammer forged? Is that what you meant?

I've never heard of a "cold formed" barrel, chum .. That aint a making making term I am familiar with ...

Don't exactly know how it applies to Mauser barrels but "cold Forming" is any process that is used to "form" the metal while "cold" as in not heated, not preheated, not red hot, no nothing.

Cut rifling is not a cold forming process as you are removing material, Same a broach cut rifling.

Typically though any material Cold Formed will work harden and that is what I think bartsche was getting at. Although it should have no affect on a rebore as they are typically cut rifled anyway.

Some years back I had an opportunity to invest in a lot of 8mm Mauser barrels that had been pulled of actions for very little money. One of the first things I did was try to get someone to rebore and rifle them. That is when I ran into the work hardening of the formed rather than cut rifling or so I was told. The story went on to say that often reboring these barrels caused barrel and tool damage as it appeared that the work hardening was not homogeneous and set up chatter.
I never had reason to doubt this till now. For all I know it still may be fact.Any other boring guys or true Mauser experts out there ? Can some one with absolute knowledge respond? Thank you for your anticipated sharing of knowledge. roger

Roger,
I'm strictly guessing here and have every confidence that I will be corrected so I'll just say it.....I doubt that any of the 8 X 57 Mauser barrels made up to 1945 (end of WWII) were anything but cut rifled barrels.

I'm not at all aware that there was any other method known at that time to rifle barrels.

What say ye.....did they button rifle barrels back in 1940s?

mauser, smle, springfields, and enfields 14/19 would all be button/broach ... in fact, shilen (button) use surplus wwII gun lathes to bore their barrels .. it is THE most value effective way to cut barrels .. drill a hole, put in a hydro puller, taper to a pattern, pretty painless ...

hammer formed barrels, of which cz 550s are, arekind "cold" formed .. rifling mandrel insert, barrels hammered.. same as rugers, btw, and sakos .. all three being creat candidates for reboring ...

the statement that "cold formed" (you see, that's not a barrel making process) barrels aren't cadidates is just, well, like saying one can't cut rectangular threads ....

quote:

mauser, smle, springfields, and enfields 14/19 would all be button/broach

Jeffe,
Are we saying that all these barrels were button rifled?

I find your wording a bit confusing.....broach to me is cutting....

button .. ever last one of them ..

thank you!

According to this article, button was invented during WWII and the Germans invented hammer forging in 1939


http://firearmshistory.blogspo...g-hammer-forged.html

quote:

Originally posted by DocEd:
According to this article, button was invented during WWII and the Germans invented hammer forging in 1939


http://firearmshistory.blogspo...g-hammer-forged.html

This would suggest that only WWII barrels were either button rifled in the US and after 1939 German barrels were hammer forged.

Is one then to assume that previous Mauser barrels from 1898 to 1939 were cut?

quote:

Originally posted by jeffeosso:
button .. ever last one of them ..

This article suggests otherwise.

quote:

Originally posted by vapodog:

quote:

Originally posted by jeffeosso:
button .. ever last one of them ..

This article suggests otherwise.

not really .. it says

quote:

Hammer forging was developed in Germany in 1939

millions made before 1939 ,,, if not 10s of millions

however, i've seen articles on the internet that suggest bHo is the greatest president ever, and from respectable sources!

IMO all US Springfield and Enfield barrels were all cut or broached (another method of cutting) until after WW2 and Bob Snapp has made lots of money over the years by reboring old Mauser barrels regardless of the original manufacturing method. In the middle '60s Bill Prator was still reboring barrels at Trinidad and he never mentioned anything about any difficulties with 'cold-formed' barrels, or indeed with any other type of manufacture. He DID caution about hard spots and inclusions causing problems but the cautions were mentioned as a general thing, not specific to any particular source or type of manufacture.

Seems to me that someone just didn't want to do the work, and gave the first excuse he could think of.
Regards, Joe

quote:

Originally posted by J.D.Steele:
IMO all US Springfield and Enfield barrels were all cut or broached (another method of cutting) until after WW2

quote:

Originally posted by jeffeosso:

quote:

Originally posted by vapodog:

quote:

Originally posted by jeffeosso:
button .. ever last one of them ..

This article suggests otherwise.

not really .. it says

quote:

Hammer forging was developed in Germany in 1939

millions made before 1939 ,,, if not 10s of millions

If buttoning was developed by Remington during WWII then all those millions of mauser barrels had to be cut....?

quote:

Originally posted by jeffeosso:
button .. ever last one of them ..

And now this from a European rifle expert:

quote:

the WW1 where all cut singlepoint or broached. During ww2 they started hammerforging. I never heard of any buttonrifeled in this period. But hammerforging was invented to speed up the process, and to reduce material cost

It now seems that NONE of the Mauser barrels were button rifled!

quote:

Originally posted by jeffeosso:
button .. ever last one of them ..

I guess this is how history gets lost, people die and in a generation or two the knowledge is mostly gone. Button rifling was introduced AFTER WW2 by Remington. I don't know if they invented it (I think so), but they were the first in the US. Broaching is cutting all the grooves at once with a stepped cutter: the broach! It was invented by the Germans between the wars (WW1 & 2) as a means of increasing the production rate of (I believe) MG34 barrels. I don't believe that any of the barrels mentioned would have been anything but traditional one groove at a time cut rifled. This is not "cold forming".

quote:

Originally posted by J.D.Steele:
IMO all US Springfield and Enfield barrels were all cut or broached (another method of cutting) until after WW2 and Bob Snapp has made lots of money over the years by reboring old Mauser barrels regardless of the original manufacturing method. In the middle '60s Bill Prator was still reboring barrels at Trinidad and he never mentioned anything about any difficulties with 'cold-formed' barrels, or indeed with any other type of manufacture. He DID caution about hard spots and inclusions causing problems but the cautions were mentioned as a general thing, not specific to any particular source or type of manufacture.

Seems to me that someone just didn't want to do the work, and gave the first excuse he could think of.
Regards, Joe

That parallels what Cliff LaBounty said to me over several conversations. He was wary of hammer forged barrels because he had some hardness issues with some of them. IIRC it was Sako barrels he declined to accept because of the failure rate he experienced.

I asked him to rebore a Sauer 200 barrel (hammer forged) for me and he agreed to try as he hadn't done one at that point. When it was done he said it "cut like butter". So I guess it isn't just the process of hammer forging but several factors together that make some forged barrels difficult to rebore and not others.

It is my understanding that the Germans developed hammer forging in WWII to increase production of machine gun barrels. The MG42 had a rate of fire of 1200 RPM. You can burn out a barrel in a hurry. I never heard it was used for Mauser 98 barrels.

It's really quite easy to distinguish between any cut-rifled tube and any buttoned or hammer-forged one; simply examine the tiny reamer machining marks down in the grooves and see which way they run. If longitudinal then it's cut or broached, if radial then it's buttoned or hammer-forged. BUT, you gotta know what the details look like and with some barrels it's hard to see.
Regards, Joe

quote:

Originally posted by J.D.Steele:
It's really quite easy to distinguish between any cut-rifled tube and any buttoned or hammer-forged one; simply examine the tiny reamer machining marks down in the grooves and see which way they run. If longitudinal then it's cut or broached, if radial then it's buttoned or hammer-forged. BUT, you gotta know what the details look like and with some barrels it's hard to see.
Regards, Joe

How does it look if you have a hammered or buttoned barrel, and it is lapped

I'm willing to eat crow on this one Although it was possible that Germany made hammer forged barrels for the 98s after 1939 my original comment included all 98s and I was wrong. But I want you to know this wasn't mt first screw up. roger

quote:

Originally posted by J.D.Steele:
It's really quite easy to distinguish between any cut-rifled tube and any buttoned or hammer-forged one; simply examine the tiny reamer machining marks down in the grooves and see which way they run. If longitudinal then it's cut or broached, if radial then it's buttoned or hammer-forged. BUT, you gotta know what the details look like and with some barrels it's hard to see.
Regards, Joe

I imagine, to keep it easy, the rifle should be unloaded while doing this...

Mike Walker of Remington was credited with developing the button rifling method in WW11. Germany started the hammer forging method in 1939. It is all on the internet if you will look.
Butch

quote:

Originally posted by tin can:

quote:

Originally posted by J.D.Steele:
It's really quite easy to distinguish between any cut-rifled tube and any buttoned or hammer-forged one; simply examine the tiny reamer machining marks down in the grooves and see which way they run. If longitudinal then it's cut or broached, if radial then it's buttoned or hammer-forged. BUT, you gotta know what the details look like and with some barrels it's hard to see.
Regards, Joe

I imagine, to keep it easy, the rifle should be unloaded while doing this...

You DO get a lot more light that way!

And, if the barrel has been lapped to death, there probably won't be any visible reamer marks unless under a glass. Depending upon how nearsighted you are and just exactly WHEN during the process the lapping was done of course. Some lap prior to rifling and some lap afterward. I've actually heard some say that ANY lapping should be unnecessary while still others strongly believe in fire-lapping, go figure.

Concerning reboring any particular barrel, IMO it's largely a crap-shoot with any of them and the owner should go with the opinion of the reborer. However, like doctors, reborers are subject to opinions and, again like doctors, you can always seek a second one from another practitioner.....
Regards, Joe

The first patent for button rifling was granted on 1 July 1925 to Lothar Walther. Lothar Walther developed this in the early 1920s to speed up the rifling process. With the issuance of the patent, The company Lothar Walther Feinwerkzeugbau started on that date. (July 1, 1925)

In the summer of 1945, the US military interviewed all the local weapons producers and related companies. CIOS was the entity that did the full investigations along with military intellegence. Prior to the US pullback in August, the patent and its information was signed over to the US Government.

The information arrived first at Springfield Armory and very shortly after, went to Remington. While others had thoughts of a similiar process, the tooling that arrived back in the US was what made the process work.

The information is available through the Freedom of Information Act. All the information of the processes that were discovered are listed and what happened to them when they got to the US. As most of the records were destroyed in Germany, most of the story can be obtained by paying for records searches.


Hammerforging.

This started in 1934 but it was not directed at rifle production. It took several years before it became really useable. Not much rifle production was done with it but machine guns from 8mm up to 20mm were done.

As the war went on materials were produced in a more hectic state and crossovers were possible.

In regular barrel production, as the war went on, materials suffered and quality was reduced and production was streamlined.

Cryogenic treatment prior to rebore will give higher chance of iniformity/accuracy in the boring process.

Oh does it!

Hell! I may have been in left field on this one but it's truly been so informative I'm glad I started it. roger

quote:

Originally posted by butchlambert:
Oh does it!

According to John Krieger it does. So much that he cryos all his blanks[in house], prior to deep hole drilling. With cryoing, his scrap rate because of excessive run-out is next to zero. Prior to using cryo, the deep-hole drilling operation produced a 30-40% scrap rate[more than .005-inch run-out].

I guess John told you that or is it mentioned on their website?
Butch

SmokingJ,
I'm sure that you are certain on your info, but Merle H. Walker, known as Mike was given US Patent# 2,383,356 for button rifling which he gave to Remington.
Butch

quote:

Originally posted by jeffeosso:
button .. ever last one of them ..

I believe you are mistaken, these barrels are all indeed broached, as in broach cut, all riflings cut to full depth in one pass by a broach.

The majority of them were cut rifling by the old method. I believe this to be one reason why the U.S. went to two groove rifling to speed up production.

quote:

Originally posted by Trax:

quote:

Originally posted by butchlambert:
Oh does it!

According to John Krieger it does. So much that he cryos all his blanks[in house], prior to deep hole drilling. With cryoing, his scrap rate because of excessive run-out is next to zero. Prior to using cryo, the deep-hole drilling operation produced a 30-40% scrap rate[more than .005-inch run-out].

And yet, somehow, (must be witchcraft!) Bill Webb's HOMEMADE rifling machine will drill about 30" or more with less than 0.004" runout! IIRC it's actually less than that, but my copy is out in the shop right now so I won't claim any closer. And I don't recall Bill mentioning any cryo.

30-40% scrap rate, huh?

IMO, only in your dreams.
Regards, Joe

quote:

Originally posted by J.D.Steele:
And yet, somehow, (must be witchcraft!) Bill Webb's HOMEMADE rifling machine will drill about 30" or more with less than 0.004" runout! IIRC it's actually less than that, but my copy is out in the shop right now so I won't claim any closer. And I don't recall Bill mentioning any cryo.

30-40% scrap rate, huh?

IMO, only in your dreams.
Regards, Joe

Feel free to take the issue up with Mr.Krieger himself.
Do you recommend Mr.Krieger use Bills Homemade rifling machine to keep the doors of his shop open?
Is Bill Webb and his gizmo capable of keeping up with production & supply on a commercial scale?

anyway, heres Bills backyard wizardry rifling machine ,...


..and heres a Pratt & Whitney rifling machine used by a number of successful commercial CRB manufacturers.

Trax, you seem to have lots of photos of things that don't belong to you.

Yes, I've seen the P&W machines before, Prator had several in his shop. They're all at least 65 years old now, last one was made during WW2. Perhaps John needed to rebuild his.

Regardless, I simply don't believe your story. It doesn't fit with what I've learned about barrel rejection rates. Even with John's practice of turning the contour first, before drilling(!), it still doesn't make sense.

No, Bill's machine isn't fast enough for production work or anywhere close to it. But a 30-40% rejection rate isn't ACCURATE enough for a precision barrel and the lost time would quickly make Bill's machine look pretty good in comparison.

I personally don't believe that John ever experienced this rejection rate, at least not due to failing to cryo his steel. It just doesn't make sense.
Regards, Joe

Here's the point of the thread.....originally

quote:

Originally posted by bartsche:
Some years back I had an opportunity to invest in a lot of 8mm Mauser barrels that had been pulled of actions for very little money. One of the first things I did was try to get someone to rebore and rifle them. That is when I ran into the work hardening of the formed rather than cut rifling or so I was told. The story went on to say that often reboring these barrels caused barrel and tool damage as it appeared that the work hardening was not homogeneous and set up chatter.
I never had reason to doubt this till now. For all I know it still may be fact.Any other boring guys or true Mauser experts out there ? Can some one with absolute knowledge respond? Thank you for your anticipated sharing of knowledge. roger

Roger.....may I take a stab at this?.....

IMO it was as previously described.....someone didn't want to do the work and grabbed the first excuse that came along.

I've run into work harnening in my lifetime and it sure is a frustration....until one discovers that maintaining sharp tools and a generous feed rate will totally prevent it. The work hardening I'm accustomed to is from my own errors.....not something previously left in the workpiece from previous machining......and it now is quite evident (contrary to Jeffeoso's testimony) that all Mauser barrels were cut and not cold formed by a button!...or even forged!

That said.....there's so little spare steel around a Mauser barrel that I'm not at all sure who would want to rebore them.....certainly not I.....reboring and rifling to .338 maybe....but then we still have those silly steps....

Maybe you was lucky to not have invested more into those barrels!!!

Roger,
The case for reboring is worth it to me on an unusual barrel that would be cheaper to rebore. Like a barrel with a rib, octagon, half octagon, or other intregral features. I do think cost wise it may not be smart on a stock mauser barrel.
Butch

quote:

Originally posted by butchlambert:
Roger,
The case for reboring is worth it to me on an unusual barrel that would be cheaper to rebore. Like a barrel with a rib, octagon, half octagon, or other intregral features. I do think cost wise it may not be smart on a stock mauser barrel.
Butch

At this period in my maturation I certainly agree with you. Back when this was going through my brain I saw all that steel and wanted to profitably salvage it.
Similar adventure when all those 6.5 Swedes with threaded muzzles were arriving in the late 80s. Designed and built a bunch of muzzle brakes. Just about broke even with the amount of sales they generated. roger