Always used 2 think the itty-bitty center dimple N middle of primer strike hole was indicative of a Kimber’s firing pin extrusion because it happened with both of friend's 1911's in .45 ACP...
That was... until my old 1911 (manufactured in 1917) started doing it last week & more noticeably last night as shown by case head pic.
My thought is the “dimple” results from an “afterstrike”... i.e. firing pin spring is weakening & this dimple occurs from a 2nd very light “rebound” contact strike allowed due 2 worn/weakened firing pin spring.
But... how can this be, since only 3,133 rounds fired since new firing pin & recoil springs were installed:scratch:.
Prior firing pin had 13,182 rounds since new when changed & never exhibited “dimple markings”.
There are no problems associated with this anomaly that I am aware of... yet anyway. Anyone know of something strange that could arise?