Home Forums Hunting & Shooting Custom Rifles & Wildcats Heat Treatment for Mauser action?

First off, Carburising IS heat treatment. Steels with enough Carbon content will through harden when heated to critical temp then quenched. Mausers, being made of low carbon steel need some additional carbon introduced in order to harden to any extent. So, early examples such as the 1909 were "Pack Hardened". What this really means that a claylike material with carbon content was packed onto the surfaces so that during the heating process, carbon would infuse onto the surface and for a few thousandths under it. New material was used on critical surfaces such as the locking lug seats, etc. Less critical surfaces got reused material.

Over the years, as temperature controls and technology improved various methods evolved to case harden. PacMet used a gas that was introduced into the oven. Time and temp dictate the depth of the case hardening.

People always talk about blowing up an action without admitting that bad things can happen long before the action lets go.

The dead horse has 9 lives (at least).

I'm with the first responder Reheat treatment as part of fixing a problem. The DWM factory was among the best in the world at its craft. Presumptively the heat treatment was a studied balance of materials, workmanship and intended use! 'If' there is a problem in which heat treatment was a contributing factor, you have a far wider issue to be addressed. Such as bolt set back; greater issue/greater remedy!

You will presumably be removing the barrel from that DWM action. 'If' a headspace gauge is convenient, check the existing headspace prior to removal. If the rifle is of original bolt, receiver and barrel (serial number match) with headspace pass, 'presumably no bolt set back. Barrel removal also affording the opportunity of a good visual inspection of the receiver bolt lug mating surfaces for visible problem indicators. All said, the old "if it ain't broke, don't fix it."

'If' you anticipate in your customizing to involve rechambering to a cartridge beyond original manufacturer's intended pressure range, I'd not go there. Another Post here suggested, utilize an action appropriate to such pressures!

Sorry if being "too elementary" here, but building a case for 'due diligence' inspection as an alternative to a seeming extreme "preventive measure" as conjuring a good idea of the moment!

Good luck!
John

Would deep cryogenic treatment do something similar ? I don't know much about that process but I know that cryogenic treatment of some metals helps make it harder without making it brittle.

kwg

You really should stick to things other than gunsmithing. "if it ain't broke, don't fix it." What a crock. What people don't take into account is that Mauser actions were heat treated (carburised) for the cartridge they were made for. The 1909 Argentine, for the 7.65x53. It was, in most instances, sufficient for that round. But, again, they were pack hardened and often the material not properly applied. If such was the case, then the action wouldn't be sufficient for the cartridge it was designed around. Gas Carburising, the current method, means all surfaces get an equal amount of carbon added. An action so "heat treated" will be plenty able to handle modern pressures.

I once acquired a a 1912 Steyr all original and with .013" lug setback. I machined the lug seats and had PacMet carburise the action. Chambered it in 9,3x62 and loaded it to 60,000 psi. Still going strong even after being loaded to pressures beyond which it was designed for.

I shall bow to your superior knowledge on the subject, which is undoubtedly more up to date and concise than mine own.

Even when PacMet was in business, carburising wasn't inexpensive but certainly compared to Blanchard's it was affordable. In the scheme of things, when taking into account the cost to build a custom rifle off of a Military Mauser actions, it was cheap insurance and well worth it. For a tome, .270's and later the .338-06 A-square were very popular requests. Even with Weatherby's sky high pressures in their .338-06 loads, setback was never an issue.

Blanchard used to be reasonable..................

Except for the pure purist, dealing with military actions as a basis for a rifle today is a case of the juice just not being worth the squeeze...............if you just gotta have a '98 based rifle, either find a decent commercial action or be prepared to dump a lot of money into something of no real value to anyone else, & that's even if you do the heavy lifting yourself.

YMMV

MM

Fug that! People buy all sorts of modern rifles then dump a sheet ton of money into them. They don't get it back when they sell. you don't build a custom to sell, you build it to use and enjoy. There are those that prioritize utility over all else, then there are those that want utility and good looks. There's room for both.

That said, if you want to shoot "modern" or high pressure loads and don't want to heat treat, you are correct that one would be wise to select one of several later model milsurp actions or a good commercial action to start with.

Well, suit yourself.

I still have 2 Mausers that I built for myself & pit a lot into, such as fully reshaped/replaced trigger-guards, as I really don't want to sell them to anyone for a variety of reasons, but anyone that I would leave them to will have no real appreciation of them or even an appreciation for Mausers in general.

So I won't be building any more, but I still have 4 or 5 actions that I've already welded new bolt handles on, that you, or anyone else that wants to build on one, are welcome to buy for a reasonable price.

2 are pristine 1909's & 2-3 are VZ24's in average shape.

MM

According to Z1R...
***

Responding z1R. 'IF sticking to my own profession': Factual predicate of the O/P introducing his question of "reheat treating viability/desirability. He did not introduce any issue of "rechambering, much less "hot loads". The rechamber inference as introduced in this Thread as undisputedly typical adjunct of moving from obsolete, marginally available Argentine chambering to more versatile and available one. That inference adopted as yet further exploited in moved to "hot chamberings" into issues of "detrimental reliance" upon reheat treatment to 'feel good illusory reliance.

The "issue here addressed" as contemplating reheat treating in manner or effect in material compensation for "hot loads" as rebarrel process may offer lure of such chamberings as collateral moment of opportunity.

Here Alleging there is no "reasonable Assumption" in law or fact" that a rifle over a century old was ever contemplated by the manufacturer to be subject materially greater stresses in such distant future of "use". Collaterally, that their product was ever designed or manufactured with safety margins intended to tolerate such functional "pressure vessel" new-vista forces. Forces applicable in manner of instantaneous 'hammer force detonation shock'. Amplified context with possibility of 40K anticipated working PSI up to 60K working, as 50% increase beyond manufactured "daily use designs", defined as "overloads".

Conclusion, such reheat treating 'may be a useful 'adjunct', or not'. Yet 'if so', arising to no more than "contributing factor" in "catastrophic failure" deterrence. Last as exemplary, "metal manufacture era acceptable negatives of "inclusions or voids". Entirely tolerable at 40K PSI, may be entirely intolerable at said full 50% excess loads arising to 60K.

So! Achieving the "context" you suggested K1R as also boring the "S" out of our audience here, as advancing a proposition in my professional context as stated "in terms of law".

Twenty minutes, off the top of my head, not intended nor to be taken as "legal guidance" whatsoever!

A postscript as war story in respect of my "If it ain't broke, don't fix it." My wife with her classic Jaguar. The dealer service department "Repair by progressive "fix it with new parts substitution, until finding what's broke! Typically by then, the client!

Best!
John

blaah blaah blaaaaaa

That has to be a new record for useless & idiotic posts........................

MM

Huh???

Referring to that fuckwit iskra who is as usual waffling on and saying nothing.

I think we are supposed to be impressed that he's a lawyer. Unless he's become a SME by litigating a pile of DWM product liability cases, that fact has zero relevance here.

Why am I reminded of Branden and Camela ?

Yes indeed.

FWIW a couple of comments:

Pack carburising is not that different from gas carburising. In pack carburising a source of carbon (charred leather was often used) is packed around the workpices, in a close chamber. Carbon diffuses into the metal surfact to a degree controlled by time and temperature. Gas carburising simply uses a gaseous source of carbon. Salt baths are yet a third method, using carbob-containing molten salts (cyanide, typically). If clay or a similar refractory is used it is not typically to carry the carbon, but the opposite: masking areas you don't want carburised. The main advantage modern processors have is process control, but it is a pretty simple process, hundreds of years old in the case of pack carburising. The point of the exercise is to create a thin, wear resistant surface. The strength and toughness comes from the comparatively soft substrate, and the Mausers were designed with this in mind.

The risk of doing it over is of creating distortion or cracking. Unless you had good evidence that a wear surface, such as the lug seats, was soft, it wouldn't be something I'd do.

FWIW Rockwell C hardness testing is of no value here. As JStuart said, the indenter (technically it is called a brale) will push through the thin case, so the test will not tell you anything useful. A file is probably the simplest and best non-destructive test.

No, cryogenic quenching would be a WOFTAM. It has no application here.

Its application is to dealing with retained austenite at room temperature in certain die steels, by driving the martensite transformation to completion when this isn't achieved at room temperature. For a while there was a bit of a fad for doing it to rifle barrels, which was no more than snake oil.