How Do Gun Silencers Work?

Video Transcript

"Firearm silencers, how they work and they're really pretty simple. Up until about 1934 they were great fun. They were polite to use a silencer on your firearm. In some parts of Europe it is considered impolite to go shooting without a silencer on your firearm, so much noise you know, bothers us. Here in the United States since 1934 silencers have been regulated. They're not illegal in every state it depends on state laws but according to Federal law they're not illegal, they're simply regulated and taxed. We're going to talk about how they work and to put it simply a firearm silencer is a device that extracts as much noise as possible which means enough gas to relieve the majority of the noise that is made by the gas expanding as it leaves the barrel. There are holes usually drilled in the barrel or in the silencer itself. That silencer is a larger tube than the barrel and has what we call baffles in it. They're usually pieces of metal or fiber that are spaced down the length of that silencer that help divert the gas sort of like a brillo pad. It diffuses the sound in the gas so that when that bullet leaves the end of the silencer you don't hear that huge explosion of the expanding gas because the gas has to a great portion been diverted inside that silencer and held within. As it expands it expands inside instead of out into the air. They do reduce the velocity of the bullet somewhat but not significantly enough to make a difference. Basically that's a simple way of how they work. They divert the gas from expanding out the end of the barrel forcing it to expand inside the chamber of the silencer. It is much quieter when that bullet leaves the barrel. To make it a little more silent, two things are necessary. One of them is a locked breech such as a bolt action rifle or a single shot pistol and that way there is no chance of any gas escaping as the breech goes to the rear and what they call subsonic bullets, cartridges that are loaded to a low enough capacity of powder when the bullet travels through the air it does not break the speed of sound and therefore you don't hear that crack and basically that's how silencers work."