After surviving the desert, Tuco comes to a gun store. He assembles a Colt Navy revolver, a Civil War era cap and ball pistol, which fires using loose powder and a lead ball. He then proceeds to place cartridges in this pistol which would not be available for ten more years after the Civil War. This mistake is repeated throughout the movie, including the final gunfight. In the final gunfight, Angel Eyes is wearing a Remington cap and ball pistol, on a gun belt loaded with cartridges which, again, would not be in use for another decade. Also, it would be virtually impossible for Blondie to have unloaded Tuco's cap and ball gun during the night, since he would have to dig out the ball and powder.