I really don't know why I've taken an interest in this thread other than the mystery value which for me is high. Based on Kevin's list of attributes for the Aircrewman of suspect guns vintage, I made the below comparisons.
• C prefix serial numbers (~40,000) AF Contract No: DA-19-059-ORD-1546
o 5 screw KA frames, some with 6th bug screw. (Applicable)
o 4 screw KA frames later (1st observed is C269249).
o Bolster bushing dropped at some point. (Applicable to suspect model)
o PROPERTY OF U.S. AIR FORCE on back strap. (Applicable)
o U.S. only on back strap towards end of production. C402350 1st observed. (N/Applicable)
o A few unaltered revolvers have been observed with no back strap markings. (N/Applicable)
o C prefix serial number on butt. No A.F. No. The six digits of the commercial serial number were stamped on the flat on the bottom of the barrel, on the rear face of the cylinder, on the front of the extractor star, and on the rear face of the yoke. (Current pics show three out of the five) Although I may have missed something.
o A matching four-digit assembly number was applied to the left side of the frame opposite the yoke, on the yoke opposite the frame, and inside the side plate.(Current pics only show one of the three locations) Pics of the suspect gun don't show the yoke opposite the frame, nor inside the side plate.
o Standard S&W medallions in stocks, right stock serial numbered. (Not Yet Addressed)
o REVOLVER, LIGHT WEIGHT, M 13 on top strap. (Applicable)
o Spaces taken out around C277238 (1st observed). (Not Applicable for S/N)
o .38 SPL. CTG. on right side of barrel. (Applicable)
o SMITH & WESSON on left side of barrel. (Applicable)
o Barrel markings reverse at about C367647 (1st observed). (Not Applicable for S/N)
o P factory proof mark above the front of the trigger guard on the left side. (Applicable)
o 3 variations of thumb latch. (Suspect gun thumb latch not ruled out)
o Blue/anodized black finish. (Applicable)
I don't see anything that currently rules the suspect gun totally out of being an authentic Aircrewman. Also taken into consideration is the serial number range provided in the Roy Jinks letter. Note: I going to presume that all Aircrewman had alloy cylinders as does the suspect gun. Question: Based on what we know about the suspect gun what is the definitive proof? hardcase60