firing pin

[M/W]

Lets talk firing pins. I have started to make a firing pin and have some questions.

What material is everyone using? I am turning mine using o2 drill rod. and I can it get heat treated at work.

How long? I'm working on this one.

What is the diameter? To large and it's to heavy. To small and it won't be strong enough.

What spring are you using to push the pin back?

One last question. Is it the bolt making contact with the buffer that makes the spent shell eject?

[huntsinmtns]

M/W,

I tried the O-1 even heat treated it failed, instead I went to core pins 1/8" O.D. they are already ht'd 54-56 RC you can turn your firing pin point with carbide tooling. Approx. length to start is 6.625" depending on your hammer location from grip mounting.
The spring is a whole other story but I have using wire dia. of .025-.028 and trim to length of where you put your fp retainer.


GR

[huntsinmtns]

Forgot to add drill out your buffer about 3/16-1/4" in the center and put some draft on it so as you fp will not hit side wall.

[Jason]

how deep should you drill out the buffer for the firing pin?

[huntsinmtns]

Jason,

depends on how much firing pin is sticking out the back of original bolt body, I have found that 3/16" to 1/4" works well.

GR

[Ken.Abt]

If it helps BRP went through this. They gave up on drill rod/tool steel and are using 4140 now.

[M/W]

Well I liberated a few core pins from work the other day. I haven't had time to mess with it much. Maybe this weekend I'll try to fit a firing pin to my bolt.