I have tried shortening Keystone's titanium firing pins to function as inertia firing pins to stop breakage HOWEVER, at least once a mag in full-auto I get a light primer hit. Perhaps the titanium pins are too light to reliably function as an inertia system pins? Has anyone had 100% success converting a titanium firing pin to the inertial system described here: http://www.machinegunboards.com/forums/index.php?showtopic=8854