Why Are They Called Silencers? Do They Get As Quiet As the Movies?

Alright if you’re American you probably have a lot more firearms knowledge than is healthy considering how ingrained firearms culture is in the states. Guns are kind of everywhere in media, so picking up a couple bits here and there. Heck, even the military picks up stuff for movies, the shootout scene in Heat (1995) is used by Marines for training. Anyway, you’re probably here because there’s a new John Wick or you just saw an action movie and wondered what the big paper-towel roll on the end of everyone’s guns was and how it made them all quiet. You might hear them called “silencers,” but why are they called silencers anyway?

Short answer: Things are loud

Alright, alright, alright, you got us. They’re not necessarily called silencers, and you were probably getting worked up over it. The long tube your favorite action hero or spy is screwing onto the end of their gun is more accurately called a suppressor. There’s actually a very simple reason: since you can’t make a gun silent, it’s not an accurate name. Both terms are used more interchangeably in common speech, but we’ll stick with suppressor. 

But… if they can’t make guns whisper quiet like this scene in John Wick 2 (2017), what’s the point?

Bullets are loud. Partly because there’s an explosion inside the gun that makes the bullet go, and also because bullets (generally) travel faster than the speed of sound. Most firearms will produce between 150 and 160 decibels when discharged. Some sources say 140 decibels, but anything above 140 decibels without hearing protection is already bad news bears. So uh… it kind of doesn’t matter for the purposes of arguing “guns are loud.” Anything at 125 decibels or above can cause pain. 140 decibels is where you start opening the door to permanent ear damage. 

For reference, a normal conversation is somewhere around 60-70 decibels. Just a heads up, the difference between 140 and 150 decibels is actually a lot. The scale increases exponentially, so an increase in 10 decibels would sound twice as loud. In other words, a 150 decibel sound will sound twice as loud as a 140 decibel sound. 

So what’s the point?

When mitigating the sound of a firearm, there are two things you have to account for when it comes to your hearing. First is the ignition of the gunpowder and expansion of gasses inside the gun propelling the bullet. Second is the bullet breaking the sound barrier as it travels through the air. Suppressors can only handle the first bit, since the breaking of the sound barrier happens outside. Broadly, they handle this by containing all the expanding gasses that come out of a gun in a large volume, so when the gasses come out of the gun they’re dispersed a bit more and make less sound. 

Suppressors can reduce the decibel level of a firearm discharge by 20-30 decibels, which can put you just under “dangerous for your hearing without protection,” and this is why you might see suppressors marketed as “hearing safe.” It’s still a bad idea to go without hearing protection through repeated and long term exposure, as suppressed gunshots regularly go above 130 decibels anyway. It’s also important to remember that shooting indoors makes all of these issues worse, since the sound waves will be bouncing off the walls and back into your head. Long short, suppressors will help protect your hearing, but you might not want to rely on one exclusively. 

A suppressor will also conceal the muzzle flash from firing a gun. We probably don’t have to explain the applications of hiding the bright light from your gun when you fire it. 

But can we go quieter?

So suppressors don’t deal with the little sonic boom bullets make, and that’s a property of the bullet. If you’re a step ahead, you might be screaming about the use of subsonic ammunition. That’s a bullet that goes slower than the speed of sound, and thus gets rid of the “crack” that accompanies other munitions. Combined with a suppressor, this can reduce the sound of a firearm by up to 45 decibels. 

You’re now probably wondering what the boundaries of volume are here, and we do know what the quietest gun was. No, we’re not going to pull a fast one and say “we bought a single bullet and threw it really hard at the office wall.” 

Enter the De Lisle carbine, used by the Brits during WWII. The De Lisle measured at 85.5 decibels when fired (at least with the equipment they had at the time), which is comparable to what city traffic sounds like from the inside of your car or a blender. That’s pretty quiet, but even quieter was the Welrod pistol. Also British, and also designed in the 1940s. A refurbished Welrod could get as quiet as 73 decibels, which is about as loud as someone inappropriately using their outside voice from five feet away. Stand a reasonable distance away, and you’re pretty close to Hollywood quiet. It wasn’t a very sustainable design though, as the Welrod would need to have many of its components replaced after 10 rounds were fired, or it wouldn’t be anywhere near as effective. 

So between the De Lisle and the Welrod, you can actually get a lot closer to Hollywood quiet than you might have thought initially. You should probably still consider hearing protection if you don’t want tinnitus, though. 

Speaking of John Wick and Keanu Reeves, see if you know his stuff here.