Standard revolvers typically have 6 slot cylinders. Of course, it is not a rule – different designs allow for different cylinder capacities. However, most of the easily recognizable revolvers have 6 chambers. For example, those used by 19th century cowboys were typically like that. But did you know that it is recommended to load these older revolvers with 6 cartridges only? In fact, even cowboys didn’t load them fully.
The problem is that back in the day revolvers had pretty simple trigger mechanisms. They were so-called single action – you had to cock the hammer and then you could pull the trigger. This is why in old movies you see cowboys using one hand to cock the gun and another one to aim and shoot. The striking pin in these revolvers was integrated with the hammer. It was a good and simple design, but it did have a pretty dangerous flaw.
Of course, safety mechanisms were not really there yet. This means that a hammer in its resting position was actually resting with the striking pin right on the cartridge. There is no other way of saying it – a little bump on the hammer could cause an unwanted shot. And there were many opportunities for such bumps. Can you imagine a cowboy riding on a horse with the revolver flopping around? An accident was waiting to happen.
This is why up to this day it is recommended to load 5 rounds only and to leave one chamber empty. Then the empty chamber can be turned to be right in front of the hammer. In this way the revolver will never shoot by accident. Of course you can load all 6 if you are in a shooting range or are no planning on going anywhere. But if you are about to go on a walk or ride a horse, you should not fill up the cylinder.
Unless, of course, you have a more complex double-action revolver. “Double action” infers that the trigger pulls the hammer and then releases it. This kind of mechanism allows for quicker shooting (you don’t have to cock it), but the trigger has a longer throw and is heavier, which negatively influences accuracy. That is why when accuracy matters the most people still cock even the double action revolvers.
The best part is that these kind of mechanisms usually have a separate frame-mounted firing pin, which is a lot safer. After pulling the trigger the hammer hits a transfer block, which hits the firing pin, causing the gun to shoot. If you don’t pull the trigger, the transfer block is simply not there. This means that lowered hammer is not resting on the cartridge and no bump will cause the gun to fire.
Of course, this goes without saying – you take care about your own gun’s safety. Get to know it better and find out if it has a transfer block or maybe even a hammer block (a mechanism that blocks the hammer from falling accidentally). But now you know why cowboys only loaded 5 rounds in their revolvers.
By the way, there is a legend that cowboys had a rolled up bill in the sixth chamber to pay the undertaker in case they die. This is, of course, a myth, because refusing to use your sixth slot at a shootout would be stupid. Also, that bill would burn pretty quickly from all the hot gasses escaping the cylinder.