R.Marshall,
You can get another firing pin and modify it, but you should keep the one that is in it as it is now. The last photo above shows the firing pin alone has plenty protrusion. Other photos show much less protrusion with the assembled bolt. I don't remember that you measured the protrusion, even though you have a dial caliper. I have found from making other firing pins that you must have enough protrusion that the primer stops the forward motion rather than the pin "bottoming out" on something. This transfers the energy to the primer, rather than some part of the rifle. Let us know what the problem is when you find it.
Mike
