Gun parts metal and hardness

Ernie Swanson

My brother is planning a build on some single shot 22's and I just thought I would throw this on here in case anyone can give some insight.

What is good steel to use for parts like the receiver, hammer, firing pin, and anything else that needs to be hardened?

Also what hardness's do these parts need to be?

He is right now mocking some parts up in S7 and plans on a rc of around 50.
does that sound right?

thanks for any help!!
Yeah I am kinda hoping he will chime in!!

I wanted to put it up in the forum in case anyone else has any thoughts!!
I'm not certain about the other parts but receivers are made from a variety of materials including aircraft grade aluminum.

A starting point would be 4140. For a .22 you could probably get away with almost any high grade steel .But I'm no gunsmith so take with a large grain of salt.

You also want to take into consideration the thickness of the wall etc when calculating your pressures for the receiver. Too thin a wall could be a catastrophe even in a .22

I'm a member of several gun boards. I'll do some checking on this for you. Might take a day or two to get a good answer.
I heard my name over here.

Cool project. I'd love to see some progress pictures if you can swing it.
I mostly use 0-1 high carbon steel and temper the parts back for their intended purpose. I use 1095 for springs and temper them at 47-49 rc. The hammer and trigger need to be higher than that so the sear wont round off with use. I go to about 53-55 rc. You can use low carbon 1018 and case harden too. Many gun smiths do that but the hard shell from case hardening is only about .004-.005" deep and can wear the sear eventually. I use 1018 for the frame generally. 4140 is nice but may need to be annealed before machine work can be performed. 1018 engraves cleaner than 4140.

If you have a Brownells catalog you can read about the hammers and triggers etc that they sell and often they tell how hard they are. Its a great book for the gun maker. There is a wealth of info in there plus everything ya need for heat treating, bluing, checkering, engraving etc etc.
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Mr Bruce is again, dead on. Get a Brownells cat,as well as a Numrich catalog. Anything you need will be inside somewhere, when Im rebuilding a firearm, thats my bibles.
Thanks guys, I will pass this info on to my brother!! Maybe I can talk him into taking some pics!!

I think he is set on using S7 but we will see.