I just bought, but have not yet received, an Oberndorf Mauser action which was barreled by Westley Richards and converted by them to use .303 British ammunition. It is not one of the original 100 slant box actions made for Rigby, but uses a special magazine box which allows it to feed a rimmed cartridge.

Problem is, the rifle was in a fire, which resulted in the stock being charred to the point that it was discarded. The seller, however, reports the springs to still be functional.

My feeling is that if the action was not subjected to enough heat to entirely destroy the stock and ruin the springs, then the heat treatment has probably not been compromised. Is this a false conclusion?

If so, where should I send it to be re-heat treated?

If the springs are good, the receiver is too.
But if you are just paranoid, send it to Blanchard; you have to tell them what you want done; they won't do anything unless you do.
I specify a hardness of RC 35-40 and a case depth of .010-.015.

If a file will cut the metal, then it's been annealed to a significant degree. The annealing process starts at 450 degrees which is not very hot (pizza oven hot) and polished metal will turn golden brown. You have to get it over 750 to compromise a spring (molten lead heat) and polished metal is light blue at this point. I would check the extractor. That's supposed to be heat treated like a spring and should be hard enough that you might be able to scratch it with a file but not very much cutting going on. The bolt stop spring ditto. The action itself is made of steel that does not through harden anyway, only the case layer hardens, but if heated and cooled very slowly the crystal structure will be affected which is probably not a good thing. The other problem is metal that has been in a fire rusts rather readily as there is no oil left and there is often water around after a fire. If it's rusty you may have to polish and recase anyway.

Your files must be dull because I can cut most many Mauser receivers with a file. In fact, just now I cut a 1934 Oberndorf receiver just to do it.
And any nickel or chrome moly one.

How do you get a file into the receiver lug abutments where the case hardness on a mild/medium carbon steel counts?

We go round and round with Mausers and their century ago hit and miss horse hoof and old leather 'hardening by eyeball' techniques and results.

If you send it to Blanchards at least you will know it was properly hardened by a modern method..... and hopefully doesn't come back warped.

Xausa, I think it is probably fine although I would recommend you have it assessed by a Mauser specialist.
Someone like Lon Paul, he’s been unlucky enough to experience this scenario first hand.

I have sent at least 20 to Blanchards; none were warped in any way. They have the procedure down pat. Some were sent that didn't need it, but the owner just wanted it, some did.

quote:

Originally posted by dpcd:
If the springs are good, the receiver is too.
But if you are just paranoid, send it to Blanchard; you have to tell them what you want done; they won't do anything unless you do.
I specify a hardness of RC 35-40 and a case depth of .010-.015.

Hmmm just got one back... spec sheet with action says 35RC and case depth of 015-025 Any thoughts?

I stopped into Blanchards about 15 years ago and spoke to them about the process of reheat treating mausers.

I asked about warpage, they said some warped and they didn't know why.

Maybe they improved or refined the process since then? I don't know.

Thoughts? Anything is better than RC25 that some early Mausers have.

Slightly off the main topic, but does anyone here know if this applies to Siamese 98 type actions? I have one that has had the cover holes welded up and the whole thing polished. Does it need heat treating? My plan is to make a 45-70 with it.

quote:

Originally posted by Duane Wiebe (CG&R):

quote:

Originally posted by dpcd:
If the springs are good, the receiver is too.
But if you are just paranoid, send it to Blanchard; you have to tell them what you want done; they won't do anything unless you do.
I specify a hardness of RC 35-40 and a case depth of .010-.015.

Hmmm just got one back... spec sheet with action says 35RC and case depth of 015-025 Any thoughts?

This plus whatever depth achieved at the
factory would be more than enough. The average seems to be about a total of .032" in the lug seat area.

Siamese are very good as is, and plenty for a 45-70; however, who knows what your welder did to it.....that will range from careful TIG welding, to what I have actually seen; gas welding that anneals the whole thing.

We don't know what Mauser, DWM, Loewe, Steyr, or FN did pre WWI. If someone says they know, I would say they are lying. I would love to see documentation that says I am wrong. So far no one has been able to show it.

I read and hear lots of anecdotal stories, lots of stated RC's, but no documentation presented.

I read at one point that Burgess destroyed upwards of 200 1909 receivers perfecting the Burgess method, but I have never been able to find anyone that has any documentation that shows what was found, or what the ultimate method was.

xausa, I would recommend having the entire gun inspected. For the money, I would have the receiver and the bolt re hardened. In the grand scheme of things it is cheap insurance.

I have a SimsonWerke DSM that the seller neglected to tell me was in a fire at some point. The charred interior of the stock was a clear indicator. All of the springs still work, the gun fires without issue, extracts etc. Everything is dead soft. Not much of an issue since it is a 22, and not much of an issue since it got torn down for a shop test action. Remember spring steel is high carbon, your action is low carbon.

Because of our other discussion recently on heat treatment I tore down an excellent condition 1909 with lug setback and dropped it off at my heat treater along with several other actions to cut up and analyze. Hopefully as time allows in a few weeks I will put something together that shows what documentation from Mauser is available, what we do know, and the analysis from those receivers for comparison.

Handbook for Shooters and Reloaders, P. O. Ackley, Volume II

Chapter 1 - The Strength of Military Actions
Chapter 2 - A Few causes of Blowups

45 pages. Relevant to the discussion or not, you make the call. Interesting and well worth the read if you haven't already.

Here is my recommendation; NO shooter should use any action made before WW2, and even then, I recommend they use only Remington 700s; that way, if they are careless reloaders. they won't be surprised when they pull the trigger. Certainly do not use any surplus military action; those are for wall hangers only and probably should be cut up for scrap. If you own one, do not ever shoot it with live ammo. (although I blew up an M14 one with blanks; another story)
Issue solved.

quote:

Originally posted by Fal Grunt:
We don't know what Mauser, DWM, Loewe, Steyr, or FN did pre WWI. If someone says they know, I would say they are lying. I would love to see documentation that says I am wrong. So far no one has been able to show it.

I read and hear lots of anecdotal stories, lots of stated RC's, but no documentation presented.

I read at one point that Burgess destroyed upwards of 200 1909 receivers perfecting the Burgess method, but I have never been able to find anyone that has any documentation that shows what was found, or what the ultimate method was.

xausa, I would recommend having the entire gun inspected. For the money, I would have the receiver and the bolt re hardened. In the grand scheme of things it is cheap insurance.

I have a SimsonWerke DSM that the seller neglected to tell me was in a fire at some point. The charred interior of the stock was a clear indicator. All of the springs still work, the gun fires without issue, extracts etc. Everything is dead soft. Not much of an issue since it is a 22, and not much of an issue since it got torn down for a shop test action. Remember spring steel is high carbon, your action is low carbon.

Because of our other discussion recently on heat treatment I tore down an excellent condition 1909 with lug setback and dropped it off at my heat treater along with several other actions to cut up and analyze. Hopefully as time allows in a few weeks I will put something together that shows what documentation from Mauser is available, what we do know, and the analysis from those receivers for comparison.

I have at least some of those documents sent to me directly by Tom. That reply I posted was a paraphrase of one of his statements in which he details the way in which he arrived at "his method" while working with PacMet. He elected to work with them because, at the time, Blanchards reults were unacceptable.

quote:

Originally posted by Fal Grunt:
We don't know what Mauser, DWM, Loewe, Steyr, or FN did pre WWI. If someone says they know, I would say they are lying. I would love to see documentation that says I am wrong. So far no one has been able to show it.

I think we do know from Speed's book and what Burgess wrote right here on this forum.

Mild to slightly higher carbon steel with trace alloys of little consequence were pack hardened with carbonaceous material, leather, bone, etc,, in the locations where hardness was required.

Some of that carbon laden gas deposited on other areas creating a case depth that varied over the receiver.

The problem is all the variables of the day, the inconsistency of the carbonaceous material in carbon content and transfer, the use of recycled carbonaceous material that was depleted, inconsistent placement of material, heat treat temperatures being judged by eye, leaking pack hardening containment vessels and all the rest that go along with that heat treatment of that era.

The results some are hardened properly for as well as can be for low to medium carbon steel (a poor choice today) can be for a gun receiver and some aren't.

Mauser wasn't the only one having problems with heat treatment 120 years ago, everyone did.

Well said Doug.

Also, for the most part, the Case Hardening at the time was adequate for the powders then in use. Today's powders burn quite differently.

quote:

Originally posted by z1r:
I have at least some of those documents sent to me directly by Tom. That reply I posted was a paraphrase of one of his statements in which he details the way in which he arrived at "his method" while working with PacMet. He elected to work with them because, at the time, Blanchards results were unacceptable.

I would be very interested to see copies of these.

quote:

Originally posted by Doug W:

I think we do know from Speed's book and what Burgess wrote right here on this forum.

Mild to slightly higher carbon steel with trace alloys of little consequence were pack hardened with carbonaceous material, leather, bone, etc,, in the locations where hardness was required.

Some of that carbon laden gas deposited on other areas creating a case depth that varied over the receiver.

The problem is all the variables of the day, the inconsistency of the carbonaceous material in carbon content and transfer, the use of recycled carbonaceous material that was depleted, inconsistent placement of material, heat treat temperatures being judged by eye, leaking pack hardening containment vessels and all the rest that go along with that heat treatment of that era.

The results some are hardened properly for as well as can be for low to medium carbon steel (a poor choice today) can be for a gun receiver and some aren't.

Mauser wasn't the only one having problems with heat treatment 120 years ago, everyone did.

Doug, I don't disagree with your assessment of how they likely heat treated, the problems that we see, and the causes of it. A few of the details I would question, but for gist of it, I agree. What you wrote has been written numerous times by numerous people and is not wrong. (I'll substantiate that in a moment)

I think however you're looking at this from a "big picture" point of view where as I am looking at it from a process standpoint. We simply do not know what they were doing or how they were doing it. We can make educated guesses at the process, based on the equipment available, the technology available, and the results. The results are what raise questions as to the process. I have never seen a Brazilian 1908 with lug setback. I have never seen an Argentine 1891 with lug setback. I have never seen a Chilean 1895 or 1912 with lug setback. Not that they do not exist, I have never seen one.

If they were having problems with heat treat, they were not consistently having problems. To add to it, the more I learn about Loewe/DWM and Mauser and FN and Steyr, the more I learn that they were FAR more technologically advanced than we were here in the US. At least compared to Springfield Armory.

To validate what you said above, but to also prove my point, I have included the following. Mr. Speed and I have been corresponding almost daily about this topic for the last week. This is part of what he wrote to me 3 days ago.

"so far have not found any pre WW1 specs on heat treatment or hardening..."

He has not been able to find any specifics on the process, the results, the analysis, the understanding, the effects, etc. Mauser was a cutting edge manufacturing firm even prior to WWI, I have no doubts there were REAMS of documentation. Unfortunately, it has not come to surface as of today.

"...but know in those days they had ovens and took main parts like receiver and placed charcoal around certain zones of material and ran temps up to unknown values and time frame then took parts out and air dried or oil baths. When finished a controlled scratch test test was done to determine if surface was hard enough etc.I only have detail docs from 1930 onwards for all parts used on 98 system etc. Little knowledge existed on actual steel type quality etc. I will look some more in some 1910 contracts that have a lot of data on spec requirements etc. Jon"

One of the reasons I really enjoy working with Jon, is you will frequently see or hear him say, let the documents do the talking. Not that documents are proof, but typically they tell a much more accurate story.

POST WWI is a whole different story. Jon has been able to send me several documents, which I plan on sharing as soon as I get my receivers back from heat treat. If z1r wants to include Burgess's documentation I will look through it and most likely include it to help further tell the story.

I have tried "googling" the sight to find more posts by Burgess, but I have not succeeded yet. If anyone else has any of Burgess's documentation, feel free to share it.

And if someone stumbles upon the Holy Grail of heat treatment specs, then what?

Obviously if there were sound and valid specs they weren't followed or couldn't be followed given the tech and material supplies of the day or there wouldn't be soft receivers out there.

That is all part of the randomness of end results from making millions of mausers over decades in various countries.

The academic historical exercise I can understand, but I don't see how it is going to help determine one bit if 'is my receiver hard enough'.

The answer will go from, Yeah maybe or maybe not to Yes if they followed the specs. lol

I've got an Argentine Modelo 1909 that I have planned for a build in 7x57mm. Not planning to re-heat treat it.

quote:

Originally posted by craigster:
http://forums.accuratereloadin...urgess+heat+treating

Yes, with tales of warpage.

quote:

Originally posted by Doug W:
And if someone stumbles upon the Holy Grail of heat treatment specs, then what?

Obviously if there were sound and valid specs they weren't followed or couldn't be followed given the tech and material supplies of the day or there wouldn't be soft receivers out there.

That is all part of the randomness of end results from making millions of mausers over decades in various countries.

The academic historical exercise I can understand, but I don't see how it is going to help determine one bit if 'is my receiver hard enough'.

The answer will go from, Yeah maybe or maybe not to Yes if they followed the specs. lol

It’s no different than collecting data on automobiles. It won’t tell you if your buying a good one, but it’ll help narrow the selection field. Even then it’s “yes, if they followed specs. Lol”

What area of the 98 Mauser is prone to warp if not done properly? The front ring/bolt raceways? and what can you do to correct it if it happens? I have heard about it for years but never knew exactly what area was warping.

I have a Danzig small ring that I love. It is as tight and smooth as the best commercial mausers I've handled. DPCD sent it in to be heat treated ( at my request) before being barreled to 256 Newton. A little polishing on the rails to get the black stuff off from the heat treatment, and it's right back to as wonderful as before.
I've had it back for 6-8 months. It has now had 564 full house rounds through it, and has no signs of set back. If it does at some point, I'll let you know. I'll keep putting the rounds through it until a new favorite comes along!

In my experience, right about where the thumb cut is where a bend is most likey to occur.



AS I mentioned perilously, this can be pretty well eliminated by a thick steel bolster bolted to the bottom of he action to bridge that thumb cut

Roger Green does the same thing...no more warp

I seldom had any issues with Pac Met even without
the bolster,,,Blanchard does deeper case...perhaps that may be a contributing factor..just a guess

Duane, do you send it to Blanchards with the bolster attached?

He can answer, but I do not attach anything, never had a problem and have sent them at least 20 over the past 4 years.

quote:

Originally posted by dpcd:
Your files must be dull because I can cut most many Mauser receivers with a file. In fact, just now I cut a 1934 Oberndorf receiver just to do it.
And any nickel or chrome moly one.

Nickel and CM receivers are not case hardened, they are heat treated to a particular hardness and the through-harden like springs. Mausers were made with mild steel (which does not have enough carbon content to through-harden) and case hardened. A file will not cut case hardened steel unless it has been annealed. This is why you do your engraving BEFORE you case harden, and why you have to anneal a case hardened part before recutting engraving. Many case hardening procedures require a mild anneal afterward to prevent cracking of the case layer, which is said to be "glass hard". This is usually a 400 or 450 degree anneal. This leaves the case a bit softer/more ductile, but not much.

quote:

Originally posted by Doug W:
How do you get a file into the receiver lug abutments where the case hardness on a mild/medium carbon steel counts?

You take the barrel off.

RC 35 is rather soft .. especially for a case-hardened surface. A file is at least RC 55. I suspect that 35 figure is the internal core hardness and that's not very hard at all. The case layer should be about RC 50 after anneal or it's a waste of time, not going to add much wear resistance or strength.

Really? A file will not cut case hardened steel?
Come over and we can file on any number of at least 100 Mauser receivers of all makes and years. And I have many that you can't cut. Nickel steel 1917s, most of them, you can't cut. Some you can.
I am well aware of the heat treatment given to modern steels. And 8620, a CM steel, widely used on single shots, can indeed, and often is, case hardened. It is not the CM, it is the low .2 points of carbon in it that allows that.

A couple of corrections.

First carbon doesn't matter in hardening beyond max hardness. Hardening depth is a function of hardenability and that is driven by alloy content. 1030 will harden in thin sections, but you need to add alloy to get it to harden in thicker sections. Hence 4130 was created by adding chrome and moly.

Mausers were mostly made of 1030 plain carbon steels. This can be checked from a few sources that actually cut them apart and analyzed them. They were simple carbon manganese steel. Carbon for strength and manganese to control sulfur which was prevalent due to the steel making practices of the time. Desulfurization wasn't what it is today. And sulfur, if left unchecked, causes brittle steel.

You can't measure the hardness of the case without cutting it apart and using a micro hardness technique. What is reported by a heat treater is a composite hardness combining the case and underlying base metal. So 35 Rc combines the case and underlying material. You correlate that number to the microstructure and Bob's your uncle.

Good heat treaters put a control coupon in each batch and cut that apart to check case depth, etc as their quality check.

Files are made of 1095 and are heat treated to 58-60 Rc. We used to supply Nicholson until they moved the file manufacturing to Brazil.

Jeremy

Good information.

quote:

Originally posted by Russ Gould:

quote:

Originally posted by Doug W:
How do you get a file into the receiver lug abutments where the case hardness on a mild/medium carbon steel counts?

You take the barrel off.

RC 35 is rather soft .. especially for a case-hardened surface. A file is at least RC 55. I suspect that 35 figure is the internal core hardness and that's not very hard at all. The case layer should be about RC 50 after anneal or it's a waste of time, not going to add much wear resistance or strength.

OK, here is a VZ24, that wasn't annealed or anything else, with zero sign of setback that I previously sawed in half and can file right through the breeching collar, easily.
I have lots of 4140 hardened to 36 Rc and I would say this collar is quite a bit softer.



So what did this tell us?
Is the receiver too soft?
Case too thin?
Will it be adequate for my super duper round?

From my experience there is a difference between the older pack hardened ones,ie pre WW1, and the later Durferrit or cyanide salt bath hardened ones.

Pack hardened- Very selective hardening of the lug recesses and wear areas only, the exterior was left unhardened. The case was very hard, not fileable, almost like it was left in the as- quenched state.
Case depth probably varied somewhat, maybe around 010"or so. But it was hard as the hobs of hell, you can't file it so surface hardness must be up around 60RC transitioning through to a low RC number at the core. This is where the Rockwell C scale starts to become unreliable for testing carburised samples.

Durferrit salt bath hardened- They were able to safely achieve much deeper case, probably up to around 020".
Because of this considerably deeper carbon penetration, after the quench the temper was drawn back a lot further resulting in a thicker but softer case, with a more gradual transition to the core. Rockwell numbers are most likely in the 30's, similar to the Burgess method used today.
These actions are fileable in the lug recesses as illustrated by Dougs VZ24, essentially having the properties of a through hardened part.

quote:

Originally posted by metal:
Pack hardened- Very selective hardening of the lug recesses and wear areas only, the exterior was left unhardened. The case was very hard, not fileable, almost like it was left in the as quenched state.
Case depth probably varied somewhat, maybe around 010"or so. But it was hard as the hobs of hell, you can't file it so surface hardness must be up around 60RC transitioning through to a low RC number at the core. This is where the Rockwell C scale starts to become unreliable for testing carburised samples.

I had a 1940s US made milling machine spindle that was case hardened.
The oil seals cut grooves right through the case. It had other damage where the tooling mounted too.

A file skipped right off the surface but the hardness could not be determined because the case was so thin the tester penetrating ball just broke through it giving very low readings.

This was made in the US 50 years after Mauser was using animal products to pack harden and shows yet again the short comings of case hardening mild steel.

I made the replacement out of 4140, had it hardened and tempered to about 52Rc, then ground to size.

Case hardened mild steel is a poor substitute for properly hardened alloy steel. They didn't have much choice 120 years ago, we do now and I question the wisdom and economics of trying to bring inferior material up to a higher, modern performance level.

True, and before Steel was cheap enough to use on large items (Bessemer process), we used Wrought Iron for everything including barrels and frames. It works fine with low pressures.
We are taking 19th century technology and materials and trying to put 21st century pressures into them. Amazingly enough, it works 99.99 percent of the time.

quote:

Originally posted by dpcd:
He can answer, but I do not attach anything, never had a problem and have sent them at least 20 over the past 4 years.

Thank you.I will answer,! The steel bolster is tightly bolted to the bottom of the action from tang to just aft of the feed ramp..and left there during the heat treat process. I use a block approx 1" x 1/2".

Like the folks at Blanchard say"Some warp, some don't and we don't know why"

Sooo..... Why not use it...like wearing a belt AND suspenders


Just for Doug's info...the prestigious FZH action is still made from 1030...adhering the time tested "hard case, soft core"