Home Forums Hunting & Shooting Gunsmithing Advice for re-heat treating Zastava Mausers.

What I don't know about hardness testing could fill volumes. That's about the range of hardness you would expect for heat treated medium carbon steel like 1035. I don't have a solid value for yield strength but it should be on the order of 78,000 psi which is enough.

Rockwell C testing involves applying a cone shaped diamond point with a 150kg (~331 pound) load and measuring the depth of penetration. So if you test over the case you can get close to the core hardness if the case is thin, something more if the case is thick. Kuhnhausen mentions this as a way to test for "overly hard" actions by which he means the case depth is greater than what he considers ideal.

In the post after yours Butch my question is answered.

I understand the receiver hardness. It was the term "case hardening"

When using a conventional Rockwell tester, if the case isn't too thick, you blow right thru it. I donn't know where they draw the line. As in the correction factors for round pieces, factoring in diameter and hardness range.

Thanks Butch and Blackhawk for clearing that up.

In the microhardness world you would take a measurement every .010", on the receiver you just cut in half to check the hardness..............:-)

I have seen 98 actions that have had the marks ground off of the receiver. To do this, you would have to grind through the case hardened layer.

Of course, the inside of the action and the lugs would still be case hardened, if they ever were, but still, it looks like grinding the crest off, and the resultant case layer, would severly weaken the action.

I sent one that had the crest ground off to Douglas and they tested it. They said it tested 0 RC, and sent it back. They would not put a barrel on it.

With the thousands of hardness and micro hardness tests I've done I've never tested THRU a case hardened part so this has been an education.

Thanks to all of you.