That was mostly before the days of good aftermarket frames and it is not unusual to find one of the SM frames that has been converted to. Does anyone recongnize this number or know where I can find out more in formation.ĭuring that time Colt made a small run of Service Model Ace pistols 22s that continued from the last serial number of the last original production run. I have seen the 'SM' designation in serial number lists, but it seems to stand for 'special model' and were made way back when. There are no numbers on the slide or the barrel. It is stamped on the right side of the frame, above, and slightly forward, of the grip. I am trying to trace the serial number, but mine does not match anything I have been able to find.
