The movies I saw them in they used single action revolvers. And they could them all day without reloading. But I did not see all their movies.
Double action revolvers, they did not have to cock the hammers to fire them, merely pull the trigger. Pull it six times and the revolver would fire six shots. An AR-15...pull the trigger 30 times, it will fire 30 shots......assault weapon, pull the trigger once and it will fire every cartridge in the magazine.