[Thor]

Legend has it that this was an occurance of an overload and the breech block being really hardened and a little brittle a shearing of the recess area occured from back pressure force from an excess high pressure gas occuring from the case (the brass part of a loaded round) pushing back on the firing pin against the retainer pin and breech block! The firing pins were redesigned in WWII with vents in the firing pins to prevent this from happening! Most of these failures would be in WWI Lugers or those that are parts guns that use the WWI Luger firing pin! ~Thor~ Unclear on the markings but I bet someone knows