Guys, quick question. On correct original Vietnam era US Air Force model 15 revolvers, were the USAF markings stamped after the pistol was blued? Or were they applied prior to being blued? TIA for any help.

While the USAF M15 isn't my focus,
IIRC the factory pulled standard 15-2's from the vault and stamped USAF on them,
Probably swapped in the wide tt/th if not already equipped as well.
I could be wrong.

I carried one for years. I believe it was before bluing as it was a government contract. Also the OSI carried the model 36 which had OSI on the side as well. The stamp was really clear that is why I say before bluing.

The unit price was also listed at like $85.00 each on the 15's, which came in a 2 inch and 4 inch. The two inch versions were mainly carried by missilemen, aircraft crews and couriers. The four inch guns mainly by Security Police. Ball ammo was issued (18 rounds) to meet NATO specs.

Has anybody seen a M36 with OSI stamped on it? That would be worth a lot of money. Is a photo available?

I was a Security Police flight armorer while in the Air Force.
The only guns that I ever saw in person were those that the agents carried. I have never seen a surplus one out on the market. The agents carried them all the time even off duty. So it was a rarity to get a good look at them.

I believe the Air Force replaced the 36's with Sig Sauer 228's (M-11), even when the Beretta M9 was issued for a short time.

Model 36-1, stamped "O.S.I."