Firing pins don't "wear". Either the bolt is not going into battery, or the firing pin is somehow jammed inside the bolt. It has been a long time since I have had a BAT apart, but if you remove the pin holding the firing pin in place and inspect the pin and the bolt, you may find your problem.
Or just sent the gun to Browning for repairs, they will fix it without switching out all the internals parts one at a time.