I lost the firing pin to my 39a when I broke the gun down to clear a jam in the field. I bought a new one from Brownell's and noticed that it did not protrude from the bolt face, so I assumed it needed fitting. I filed down the tab sticking down that stops the forward travel of the firing pin until the "tit" on the firing pin protruded from the bolt face, but the "step" down from it did not. I then fired a few rounds of Colibri into the phone book and examined the cases. The primer dent is quite pronounced and I think I may have allowed too much protrusion. The case wasn't pierced, although the rim is bent in slightly toward the bolt face. Is there an easy way to measure the protrusion? If I have too much protrusion can I file down the "tit" on the end of the pin to compensate? I'll post pictures of the brass tommorow night if you guys want to take a look.

Thanks!

It sounds like you have modified something that did not need it. The firing pin should not protrude from the bolt face or it would likely fire the cartridge upon closing. I would get a new pin, install it and test-fire the rifle before I did any modifications. I've had more expensive lessons.