 FACT: When the "bad guys" are about to shoot Bart, whom they have  just learned is the new sheriff, they are all on horseback and  aiming their handguns at Bart. All of the firearms visible are Colt  1873 Single Action Army revolvers. The mistake is that none of the  weapons are cocked. Any single action revolver will only fire after  the hammer has been moved completely to the rear. None of the guns  in question have been cocked 