Many thanks a lot for the information. I'm going to achieve out to this fellow and see what his wait moments are. Thanks! The "C" around the barrel would reveal a chrome chamber only barrel. But AFAIK, Colt marked the "C" up near the muzzle on their own early barrels, https://coltm16a1forsale45555.wikimeglio.com/9439010/top_guidelines_of_colt_combat_unit_rail_gun_45