Gun Silencers 101

Okay, first and foremost, let’s get this straight. They are suppressors, not “silencers”. They suppress the sound of the weapon being fired. They do NOT silence it (except for in Hollywood movies). Although, technically, the guy that invented them called them silencers, so I guess either/or.

A good, quality suppressor on a .22 LR, pretty much silences it. I have fired suppressed .22’s, and you literally hear the sound of the action working. You hear the ting ting of the spent shell casing bouncing on the concrete over the sound of the powder charge igniting.

However, in larger caliber weapons, there is still a noticeable sound of the weapon being fired. Although, the sound is suppressed, meaning the decibels are lowered. What is a decibel you ask?

Decibel (dB)

The level of sound is rated in decibels. A quiet sound has low decibel levels, and a loud sound has high decibel levels. Decibel levels are measure by a factor of 10. A sound 10 dB louder is ten times louder.

Most of us have heard a train horn. Those things are loud aren’t they? Well just how loud IS a train horn? A train horn is supposed to be 110dB 100 feet in front of the train.

Factors of 10

A jet at take off from 25 meters away is 150 dB. That is loud enough to rupture your eardrum. Think about how loud that is by the 10 factor. A train horn as we know, is very loud at 110 dB at 100 feet.

Every factor of 10 is 10 times louder. So starting at 110dB, 120 dB is TEN TIMES louder. That jet taking off at 150 dB, well, I don’t want to be anywhere near that.

Guns are Noisy

But we aren’t talking about trains and jets here, we are talking about guns. So just how loud are guns? A typical 9mm pistol has 160 dB! That’s not even a very big gun.

Let’s move up the scale some. A .357 magnum handgun boasts almost 165 dB. Oddly enough, the larger .44 magnum is rated at the same 165 dB as the .357 magnum is.

My .45 ACP pistol I carry is just slightly less at 157 dB. In other words, the most common handguns are louder than a jet and are all loud enough to damage your eardrums.

The most commonly used rifle cartridges all fall in between 150 and 160 dB as well. So, it’s fair to say, that pretty much any weapon you will fire has an average of 155 dB. So they are all capable of causing permanent hearing damage. This is why you should always wear hearing protection when firing weapons.


Of course, in a defensive situation you won’t be wearing any earplugs, but that’s just how it’s going to be. At least you’ll still be alive. I know from experience that the difference between firing a gun outside, and firing one in the confines of an enclosed space, like your living room or an indoor gun range, are huge.

Outside, I can fire a 9mm many times with no problems, but 1 shot inside and my ear hurts. I am sure I have caused permanent damage to my ears over the years by firing guns (and loud music).

suppressor 3


In comes the suppressor. A suppressor is a device that either attaches to the muzzle of a firearm, or is integral to the barrel.

Integral Suppressor

An integral suppressor is like the entire barrel is inside the suppressor tube. The purpose of the suppressor is to lower the decibel level of a firearm, and to lessen the muzzle blast (the fireball that comes out of the front of the barrel by burning gasses).

The Maxim Silencer

The first suppressor was designed and marketed in 1902 by Hiram P. Maxim, the son of Hiram Stevens Maxim, the inventor of a neat little device known as the machine gun. He marketed his new device as the “Maxim Silencer”. Once upon a time, you could buy a silencer/suppressor just like you could a firearm. Just order it in a magazine and have it sent to your house. Those days are gone.

Now, you usually have to buy a firearm through a federally licensed firearms dealer. Although, many states do allow face to face sales of firearms so that one person is able to sell a used firearm to another person without any paperwork. This is perfectly legal. Silencers/suppressors are a different story.


These devices fall under the national firearms act of 1934 (NFA), which means they are considered a Class III Device. This means that in order to purchase or possess one, you have to go through a rigorous background check, wait months and months, and then pay a $200 tax for each device.

Firearms Trust

Another way to legally posses a silencer/suppressor is through a firearms trust. This is often a little easier to get through the paperwork once the trust has been established, but you need to hire an attorney to get it done correctly. There has been talk of doing away with trusts, but hopefully that never happens.

A little back information is needed here. When an individual purchases a class III device, they are the only person who may possess it. When they die they can’t pass the device or firearm down to a family member because they have to be alive to sign transfer papers, so the government seizes the weapon or device. Expensive family heirlooms are lost.

A trust on the other hand, names several people, usually family members that may possess the device or weapon. So if a family member dies, the remaining trust members maintain possession of the device or firearm. Since machine guns can cost tens of thousands of dollars, this is good news for surviving family or trust members. (You don’t have to be family to be in a trust)

“Cleaning Adaptor”

A cheaper alternative to a “real” suppressor is this handy little adaptor seen in this video. You still have to treat it as a suppressor and go though the red tape, waiting period, and pay the $200 tax stamp. But this device only costs about $75-100 dollars vs 500- the sky $.

Now the thing about these adaptors, they sell the exact same thing and call it a “cleaning adaptor”. So you can buy one without the paperwork. BUT if you use it as a suppressor and have no tax stamp, you will face stiff fines and penalties. I think it’s up to $250,000 fine and 10 years in FEDERAL PRISON, and there ain’t no parole in federal prison. If you get 10 years, you do 10 years.

Here’s another, better version called a Maglite solvent trap, for “cleaning your gun”, they sell it in a kit online.

Here’s a video showing a Maglite “solvent trap” being used against its intended purpose:

Here is yet another version made with a fuel filter mounted to a .308 caliber rifle:

Legalities Aside

Now that I have bored you with details, what exactly is a suppressor? A suppressor does for a gun what a muffler does for an engine, it makes something that is very noisy much less so.

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How Does a Suppressor Work

A suppressor works by capturing the hot gasses expelled from the firearm into a chamber that is filled with baffles. Each baffle within the body, or housing of the suppressor, creates a small chamber that captures part of the expanding gasses. In this manner, by the time the projectile leaves the suppressor, there are virtually no gasses left to escape and therefore no loud bang.

Breaking the Sound Barrier

One issue with supersonic projectiles is that there is actually a “crack” as the projectile breaks the sound barrier. A tiny sonic boom, as it were. This is often rectified in .22 caliber weapons and center fire handguns by loading the round with less powder to create what is called a subsonic round.

The Subsonic Round

A subsonic round travels slower than the speed of sound, and so this eliminates the “crack,” and thus makes the weapon being suppressed even quieter. The volume of the suppressor body also plays a significant role in the devices sound suppressing capabilities. With greater volume inside the housing tube of the device, the expanding hot gasses have more area to dissipate in. Thereby trapping more of them inside the tube.

This is why a suppressor for a little .22 is about as big as a paper towel roll, and a suppressor for a .50 BMG is three feet long and 2 or 3 inches in diameter. More area, more trapped gasses, and a .50 BMG expels a LOT of gasses.

Quiet Final Shot

So, there you have it. A suppressor can be a fun toy to play with, or it can be a very necessary accessory to a tactical firearm in a combat zone. If you are sitting in a building, or on a roof picking off the bad guy, if he can’t hear the shots then it is even more difficult for him to locate the shooter.

You can go about it the right way, and purchase a suppressor legally (your class III dealer will help you with all the paperwork), or you can go behind the scenes and make your own at great risk to your freedom.

I personally enjoy freedom, sunshine, and playing with guns too much to do anything to jeopardize that. But if there ever come a SHTF scenario and laws no longer matter, my shots will be silent.

About Eric W. Eichenberger

Eric W. Eichenberger
Eric Eichenberger is an avid outdoorsman, skilled marksman, and former certified range officer and instructor with nearly 40 years experience handling and repairing firearms. A skilled craftsman with a strong love for working with his hands, Eric spent 20 years as a carpenter and custom woodworker in high end homes. As a gold and silversmith he has created hundreds of pieces of jewelry over the years using the lost wax casting method. The grandson of humble country folk, he was raised with the “do it yourself” mentality and so is accustomed to coming up with unique solutions to problems utilizing materials at hand.

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