The Ruger SR1911 series uses a Titanium firing pin with a stronger than normal firing pin spring, so that would keep them safe in case they were dropped I would think. The Colt Series 80 mechanical firing pin safety is activated by the trigger and besides Colt, Para, Remington, SIG, Taurus and others use that. Now Kimber in its II pistols uses a variation of the old Colt Swartz safety so if one ties down the grip safety the pin that activates the plunger remains up. S&W used a mechanical firing pin safety also activated by the grip safety so if one tied the grip safety down on one of those the lever that activates the plunger would remain up. Below a Colt Pre Series 80 on the left, then a Colt Series 80. Next a Kimber Series II and on the right a S&W.