On Sat, 18 Mar 2006 10:57:29 GMT, Gunner wrote:
On 17 Mar 2006 18:16:42 GMT, Dave Hinz wrote:

(4140)

Any thoughts on where I should shoot for on the
hardening?

50-52//just as a gut feeling.
Is the sear carried on the bolt?

No, but of course that leads to the followup question. The firing pin
on the 1927a1 rides with the bolt, and is a piece of 1/8" flatstock cut to
an interesting contour. I made a new one (broke the firing pin tip off
of the original one due to my sear spring reduction experiments).
However, after only a few hundred rounds, the firing pin where it mates
with the sear, is showing rounding. It's unknown alloy. An point in
trying to harden that, at least in the part which meets the sear? I'm
completely ignorant of heat treating, which is pretty obvious at this
point, but I'm thinking get that local area of the firing pin up to
cherry red or so, and quench in oil?

Without knowing the alloy, I know it's a crapshoot. But knowing the
person I got these materials from, if it's newer than 1970 technology
I'd be shocked. Any thoughts?