How do silencers on handguns work?

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How do silencers on handguns work?

In: Engineering

First off, they’re not “silencers”, that implies that they take the sound to 0. They are “suppressors” because they take the sound to a non-damaging level.

The noise of a gun shot has nothing to do with the bullet. It’s a sonic boom caused by the hot expanding gas caused by burning powder. Basically a thunder clap. A suppressor forces the hot gases into a series of chambers that gives them a sealed environment to slowly expanded, where they can’t cause a lot of noise.

Side note, they only work on sub-sonic rounds because “faster than sound” projectiles cause their own sonic boom based on speed, which occurs outside of the suppressor.

Basically a silencer reduces the amount of pressure exiting the barrel of the gun. Think of it like a balloon. If you pop it, all the pressure leaves immediately and makes a loud noise. If you untie the end of the balloon, the pressure leaves slower, resulting in less noise.

Think of it like those pointy foam walls in a musicians room to keep from pissing the neighbors off.

suppressors work the same way your car exhaust muffler works. the combustion event (whether firing the of the bullet or the firing of the gasoline mixture) produces a big gaseous shockwave. this is the “bang”. in order to remove the shockwave, we have to give it somewhere to dissipate its energy and expand into. the suppressor has a series of baffles, just like a car muffler, where the energy is dissipated. this takes the sound level of a gun from 150+db (enough to make you instantly deaf) to around 130db (about a jet engine or jackhammer)

Exactly the same way car mufflers work. They were, in fact, invented by the same guy, Hiram Percy Maxim.

The sound of a gunshot has two major components. The first is the bullet breaking the sound barrier, and silencers can’t do anything about that. The second component is the charge of rapidly expanding hot gas that exits the muzzle right behind the bullet. The gas is generated by the burning powder, and comes out moving *very* fast. This causes a very loud noise, like popping a balloon.

A firearm silencer works by redirecting the gas into expansion chambers inside the silencer that allow it to expand, cool off, and slow down before it exists the barrel. Slowing down all that gas makes the pressure wave exiting the muzzle much tamer, and brings down the noise quite a bit.

[Here’s what one looks like on the inside](https://www.range365.com/sites/range365.com/files/images/2018/08/max.ns_.1911.8.jpg)

Suppressors work by absorbing some of the shock wave the exits the barrel of the gun. It’s extremely difficult to silence a gun, given how much energy is expelled. Mostly only low caliber guns like .22 rifles can be nearly silenced. This is usually done at a cost of bullet velocity/power, which can affect its effectiveness and accuracy.