 CHAR: In the locker room at the horse race, George is seen loading  his pistol. He first makes the loading movement by pulling the slide  back and letting it retreat, then inserts the magazine. Yet the gun  would not be ready to fire like this, since you chamber the first  round with the loading movement, and you naturally cannot chamber a  round without a magazine inserted. pulling the slide back without a  magazine inserted is only done during a personal safety control, to  make sure no round is in the firing chamber, but this wouldnt make  any sense at that point of the film.