Ruger Mark I, II, III Titanium Firing Pin. Our Ruger Titanium firing pins are made from Grade 6 Titanium which is nearly 40% lighter than standard steel pins which gives them a faster lock time. This will help minimize the risk of accuracy usually compromised by weapon movement before the firing pin hits the primer. This is a drop in firing pin for the Ruger Mark I, Mark II & Mark III .22 Cal. Guns.