"...the .38 caliber Officers Model Match (OMM) was serial numbered with the Troopers"

I have a .38 OMT (1953-69) and a Trooper (1953-69) and their SNs are only a few thousand apart. It was somewhat confusing to me when I first got the OMT as I thought at that time it should have been numbered with the postwar OP (1947-69), but it wasn't even close. A little research provided the answer that the OMT and the Trooper were in the same series. There is actually very little physical difference between the two.