Old post I know, but looking at the Stembridge sight, It looks like after a machinist shortened the barrel to 4" and turned down the end of the barrel on a lathe, they then reused the original sight by again cutting the tip the barrel off, with the sight still attached, and then counter bored i...

Seeing how Indy was partial to U.S. and British Army issued handguns in both 9mm and .45 calibers, I would say still the Colt 1911, and Browning hi power. Also to include Beretta 92F, and the Sig M17. As for a revolver? I would say it would still be a Smith & Wesson with 4" barrel.