Some were direct DSC purchase guns and will have no Govt. inspection marks. I have three Commandos, all three marked differently. My 20xxx range gun has an Ordnance bomb marking on the upper left frame, my 39xxx range gun only has "P" proof marks on the upper left frame, back of the cylinder and underside of the barrel and my 47xxx range gun has nothing but the Colt factory markings. I'm still looking for a GHD inspected gun. What is your serial number range?