Stainless steel, hardened or not?

[dubber123]

While working on the trigger on my brothers new BFR, I noticed there appeared to be no noticeable hardening on the hammer and sear. Metal removal felt the same from start to finish. I am used to parts being at least surface hardened.

I am wondering if it is possible to heat treat stainless like is done with regular carbon steel, or do they alter hardness by changing the mixture in the stainless alloy itself? If stainless is able to be tempered/hardened, is there any special proceedure for doing so? The trigger job came out well, 2#, nice and crisp, but the soft feeling parts don't excite me. I would feel better if I was able to harden them for better wear resistance. Thanks.

[44man]

The parts are heat treated for maximum toughness and it is all the way through. I don't think you will ever wear them out. Just keep a little lube on the sear.

[Bass Ackward]

Search the net for information on how to heat treat.

[dubber123]

The parts are heat treated for maximum toughness and it is all the way through. I don't think you will ever wear them out. Just keep a little lube on the sear.

Well if they are heat treated all the way through, I feel better about it. This one needed quite a bit of material removed, so I thought I'd try a file, and was really surprised at how fast it cut. My brother puts a drop of Mobil1 synthetic oil on the sear every time the cleans it.

[44man]

I just shot my SBH some more and reached 57,660 rounds through it. ( I have recorded all the primers used in it.) I put a 1-1/2# trigger on it when I bought it and it hasn't changed. It has also been dry fired a few thousand times.
It shows no wear, no end shake, no more cylinder side play from the day I got it.
Since Ruger casts all the BFR parts, I sure don't worry about my BFR's either.
STP on wear surfaces! :drinks:

[S.R.Custom]

Generally speaking, stainless steels don't take hardening like regular carbon steels. The ability to harden SS varies with the alloy, and the ones that are receptive to it are actually quite brittle (not used for things like hammers).

Which is why Smith & Wesson never used stainless steel triggers and hammers on their stainless steel guns. The "stainless" triggers & hammers were actually hard-chrome plated to get the "hardened" hammer/sear surfaces. Later stainless Smiths dispensed with the stainless and chroming altogether and just used the "regular" case-hardened steel.

Which is all a roundabout way of saying if the steel feels soft, it probably is. I'd be watching the hammer/sear engagement *very* closely for wear if you've taken the creep down to zero.

[danski26]

Supermag hit the nail on the head. While it is possible to harden and even case harden stainless steel with special processes, if you are cutting parts with a file with ease then they are not "hard". In my limmited experience, all of the "bearing" fire control surfaces that I have worked on could not be touched with a file but had to be "stoned" to remove metal.

As to your question of case hardening these parts yourself, it is a special gas that inparts carbon into the stainless steel during the case hardening process to get the job done with this type of alloy. Way beyond a torch and oil quench.

Maybe a call to BFR would get some questions answered as to what specific alloy and type of stainless they use "if it is stainless" and the hardness required for function of there sear trigger hammer set-up.

Or I could be totaly wrong and the pistol will serve you well for the next 2 or 3 hundered years with no problem. :-) Good Luck.

[MtGun44]

It's not that simple.

There are two primary classes of stainless steels. One class only work hardens
(by deforming when cold, like sizing a brass case) and another heat treats just
exactly like ordinary carbon steel. Heat, quench to harden and then temper to the
get the final hardness you want, trading off some hardness to remove brittleness.

Actually, brass behavior is very similar to the non-heat hardening stainless steel
alloys. Heat and quench to soften, not harden. Work to harden.

The 300 series (non-magnetic) are the work hardening only type, and the
400 series of alloys are magnetic and heat treat normally. The 400 series
is used for knives, and many other things that need to be heat treated for
hardness. There are also some precipitation hardening alloys like 17-4 PH.

A common knife blade steel is 440. I have used heat treated
416 for some very tough gun parts, but it is very hard on cutters. I would
presume that high strength and wear resistant gun parts would use the
400 series or the PH series, but don't really know what Ruger has chosen.

I just checked my Security Six and the magnet sticks to hammer, trigger and all other
parts. Same for a folding stock Mini14, except the main tube of the folding stock
must be 300 series alloy as the magnet isn't attracted to it, but is to all other
parts. Anaconda is all magnetic as is a Dan Wesson Pointman 7 (1911).

Bill

[dubber123]

Well, I guess I will just keep an eye on it. I started with a stone, which was working fine, but this one needed quite a bit of material removal, so I tried the file, and it cut very well. You cannot "push off" the hammer no matter how hard you try, and I loaded pressure on the hammer while pulling the trigger to micro polish the surfaces, and couldn't see any wear even on the shrp edges of contact right before the sear breaks over. It may be fine, shoot it and check frequently.