Mr. Wiebe generously sent me a '96 Mauser that had been in a fire. It was heated enough to anneal everything like springs, bolt, cocking piece, etc. Every part could be easily filed. I've wondered about this case hardening thing re Mausers. I dunked the action in muriatic acid solution for a time as it was rusty and had some minimal scale. After some monkey motion everything was functional with new springs. As an experiment I took a heating tip (carburizing flame) and heated the sear to red and quenched in cold water - good as new! Then, I did same to the bolt head -same! Firing pin tip - same. A worn mill file skates over all. Hmm. OK lets do the same to the lug seats - no real discernable (to me) change. This was confirmed by taking another (Swede) action that was cut apart years ago because the barrel threads were stripped and the same treatment did NOT change, again to me, a real change in hardness by file. This has caused me to screw a 8mm barrel off a Turk into said action and have a go with a 'red pill' for the heck of it. It all makes me think.

Interesting thing.

What is the goal.

Things are slow in Ak.

That is an interesting way to test carbon content. What happens if you try the same procedure with a grade 8 bolt? That should give you something of a known data point.

If you do try a proof load, I'd suggest a long string.

"Interesting thing. What is the goal."

I've read so much about the 'heat treatment' of Mausers being along the lines of - 'steel being like 1010-1030' - and case hardened for wear. We all know that bolts can be hard as corundum as I've seldom been able to get a file to bite on a bolt, especially those made ca. a century ago. I have noticed that just about every bolt shoulder, seat, or recesses call it what you will, can get a file to bite some (however, with EVERY '94 Brazilian made by FN I have the seats are as hard as the bolt. I've also encountered an Oviedo (1896) that was the same along with two CG 96's). I've also read that once a case hardened steel is annealed it's over in terms of re-hardening. That is most certainly not the case (no pun intended) as I have found. This means that after welding a bolt handle that gets too hot that the cocking notch can be put back to hard. So I guess I'll call that a goal, as that's happened to me. Maybe one just forgets all the protections and re-hardens the aft end of the bolt?

Also, I wonder about the case hardening of the receiver itself - why not the seats as hard as the bolt, generally? Seems to me they had different procedures for different parts (duh or doh?).

So for kicks I'm gonna feed this action with an overload because things are slow here in Alaska and this will keep me out of a bar or a church. I might even learn something...I'll let you know.

Bright red then cold water quench.

I wouldn't get near that if n when fired.

Thats a BRITTLE quench!

A dull red is closer to proper tempering.

Try this with good tool steel: bright red, cold water quench. lay it on an anvil and hit it hard with a 3-5 pound hammer and see if don't shatter.

Do the same test with a dull red and it should withstand about anything you can do to it.

Read up on: proper tempering procedures

George

Judging temp by color is no way to 'heat treat'a critical part.

..I'll let you know.[/QUOTE]

please do.

I wish I could find it but I've read that the typical quench for mauser actions was that they were dumped into water out of the iron casing boxes. I'm all ears as to how a 10-20 thou depth of casing over low-carbon steel is gonna somehow turn the whole of, it through and through, into high-carbon steel let alone W-1....

I’d recommend not paying too much attention to anything related to heat treat found on the internet. The mis conceptions are as plentiful as flavors of ice cream.

Did you still want those 1891 receivers? I never heard back from you.

I'll second that; definitely do not believe anything you read about heat treatment; most of it is nonsense, and especially about Mausers. Everyone is an expert. Also why I never took a job in Small Arms (when I worked for TACOM). too many experts who were clueless. Tank Armament; the experts are real and far fewer.

I don't know where you'll find part 2 of the Double Gun Journal article. I took a NRA Summer Gunsmithing class in 2004 at Murry State College that taught the basics of CCH. It was taught by Joe Beck, who was the head of the engineering dept. then. Mr Beck was also a grad of the gunsmithing course taught there. He had taken a NRA class at Lassen, if I remember correctly, and brought back to Oklahoma what he had learned there. I have "invested" considerable time and $$$ into the subject since, but rarely turn the oven on anymore. What I do know is, a torch ain't the way to do it!

Brownells has some basic written info on CCH,,,,, used to be for the asking they'd send you a copy.

I have the DGJ articles by Gaddy on CCH. I'll dig it out if anyone wants a copy. Brownells sells the ovens and bone charcoal. Yes, it is not done with a torch and quenching heated low carbon steel does nothing.

I had my oven built at Paragon Industries in Mesquite, TX. Much nicer than Brownells (WalMart) sells, lower cost and much nicer. Digitally controlled. A company called "Ebonex" is a good source for bone charcoal. Don't remember where I sourced the wood charcoal. I fabricated my crucibles and handling equipment. Fabricated my quench tank and aeration system. And, like most other gunsmithing tasks, all want a discount or to help, or both. There are many variables involved, and each has an effect on the success of the operation. I have no real number of hours or days I 'invested' in expanding (experimenting?) on what I had learned at the Summer Gunsmithing Class, and making the needed tooling required. The only way of imparting surface hardness in a case hardening operation is to surround the 'part' with carbon rich media, heat to above 1333 deg F and quench it. The higher the temp before quench, the harder the surface. The higher the temp, the greater chance of distortion. Intricate 'parts' require blocking or bracing to minimize distortion. The duration of time the 'part' is "submerged" in the carbon bearing media, the greater the depth of the 'case'.

quote:

Originally posted by dpcd:
I have the DGJ articles by Gaddy on CCH. I'll dig it out if anyone wants a copy. Brownells sells the ovens and bone charcoal. Yes, it is not done with a torch and quenching heated low carbon steel does nothing.

Using a torch and heating low carbon steel and quenching it does do something,,,,,, it makes steam and oxidation!

quote:

What I do know is, a torch ain't the way to do it!

Do what?

quote:

Originally posted by copperlake:

quote:

What I do know is, a torch ain't the way to do it!

Do what?

It appears you are trying to treat low carbon steel like it was an medium/high carbon alloy steel. They are NOT hardened in the same manner. Pull your head out and do some real research!

One can harden low carbon steel by heating with a carbon-rich flame and quenching in water. A case of significant dept can be produced. While this technique is suitable to produce a localized wear surface, I wouldn't want to try it where strength is required.
I tried all sorts of various media for my carbon source but usually came back to bone charcoal. I just bought bone meal from a local garden center. Once, on a whim, I added powdered milk to the mix and it worked just fine (I was low on bone meal). Regards, Bill

Springfield Armory used charred leather.

quote:

It appears you are trying to treat low carbon steel like it was an medium/high carbon alloy steel. They are NOT hardened in the same manner. Pull your head out and do some real research!

You didn't even read what I did, did you? Apparently, I re-hardened the case on a bolt, sear etc. that had been completely removed in a fire. I really don't get your point.

Once apiece is carburized, the top surface is no longer low carbon and, as long as it is not so hot that the carbon is burned out, I see no reason it can't be re hardened. Might not ever feel comfortable shooting it though. Regards, Bill

quote:

Originally posted by copperlake:

quote:

It appears you are trying to treat low carbon steel like it was an medium/high carbon alloy steel. They are NOT hardened in the same manner. Pull your head out and do some real research!

You didn't even read what I did, did you? Apparently, I re-hardened the case on a bolt, sear etc. that had been completely removed in a fire. I really don't get your point.

I read through the complete thread, including your posts. How do you know the sear, bolt and firing pin are the same steel as the receiver? You don't, do you...

quote:

Originally posted by dpcd:
Springfield Armory used charred leather.

Some case hardening operations use cyanide salts Most any media that contains high concentrations of carbon could be used to case harden low carbon steel. Depend upon which is deemed 'most efficient, easiest to source, safest to use".

Three loads, IMR3031, 170 GR Hornaday RN, starting with my old Lyman 45TH, max load of 47 Gr, and up to 53. Bolt shows NO signs of distress. I'm going to unscrew the barrel (the receiver had as far as I can determine .006 setback and the chamber .010 of excess headspace) to check the guts. Knocked my setup apart with the last one..

The setback remained the same. The data from Gordon's Reloading Tool:



4,890 bar = 70,923 psi. I'll take that as a decent proof load and proof of concept, too. I loaded both a 56 and 59 gr loads but stopped myself. That was hard but obviously I was in the wreck zone as it was and I wouldn't hesitate to make this a lead shooter. In any case, I thank Mr. Wiebe for a cocking piece, trigger group, trigger guard, firing pin, bolt shroud, extractor, safety and a bolt stop. The extractor will need a little more work being spring steel. The cocking piece (as being already annealed) will be a test of shortening the pin fall distance to .375" by milling and tig brazing a bar.

ETA: I was going to anneal the bolt/receiver again and repeat the high load but it's salvageable for at least other messin' around. I have lot's of junk 93's I might do that to for a comparison.

quote:

Pull your head out and do some real research!

Seriously, I have no idea at all what you are about. Play along, you might learn something.

I don't see how case hardening the lug recesses will prevent setback. Wear, yes. Setback, no. The case is very thin.

There is a reason that common wisdom is to chamber only mild ctgs in these small ring mauser actions. There may be the exception, but the exception proves the rule.

There is no way to change the alloy the action is made of. You can change the grain structure by heat treating but that's about it. Cetain alloys you can change the phase. Mild steel is not one of them.