I made a tool from silver steel ,hardened and tempered it. Soak thread with
Kroil then place tool in chuck of a drill press ,hold bolt with soft jaws in a vice,
then with a steady downward pressure of the drill press use Tee handle of tool to screw out the striker/firing pin
The no 1 mk 3 have a 30tpi and the no4 mk 1/2 have 26 tpi BSF