Of course, everyone has seen movies where an assassin screws a “silencer” onto a pistol and when he shoots the only sound you hear is a “pfffft” and the victim falls down. Despite the fact that in Federal law, the term “silencer” is used, the term suppressor is both proper and much more accurate. With certain low-power cartridges, you can get close to what those who actually possess and use suppressors call, “Hollywood Quiet.” Close, but not quite that quiet.

Think of a firearm suppressor as being similar to a muffler on a car. If firearm suppressors were as big as car mufflers, “Hollywood Quiet” could be reality. In real life, however, suppressors reduce the sound of a firearm, but never quite “silence” it.

How quiet are they? Short answer: that depends. Bullets traveling below the speed of sound – which actually varies because of many factors – are easy to suppress. For purposes of greatest firearm noise suppression, 1000 feet per second muzzle velocity is used as the baseline for true suppression. Bullets traveling at higher speeds produce a small sonic boom, usually referred to as a “sonic crack.” This means that no matter how much you reduce the muzzle blast, if the bullet is supersonic, it still makes noise, just not as much as unsuppressed fire.

Perhaps the greatest argument for use of suppressors is hearing protection. Hearing damage and prevention thereof can be confusing when it comes to exact definitions and parameters. Some sources maintain that sustained noise levels over 85 dB can cause permanent hearing damage. Pretty well everyone agrees that noise levels over 140 dB can cause instant permanent hearing loss. The list below gives some common sounds and the approximate dB level associated with these sounds:

Normal Conversation – 60 dB
Vacuum Cleaner @3 meters – 70 dB
Jackhammer @15 meters – 100 dB
.22 Rifle @1 meter – 125 dB
.22 Pistol @1 meter -- 155 dB
Center Fire Pistol @1 meter 155 – 165 dB
Center Fire Rifle @1 meter 155 – 190 db

This writer and his wife operated a shooting range for several years. Despite the requirement of the range for hearing protection, many new shooters were put off by the muzzle blast and the noise that always seems to leak past hearing protection. While not every suppressor on every firearm is “hearing safe,” most at least make the noise behind the firearm tolerable. Even the sonic crack associated with supersonic bullets is of short duration and appears to come from downrange to the shooter. In short, suppressed firearms are much more pleasant to shoot and observe than unsuppressed firearms of similar configuration.

A common question is about accuracy. Actually, suppressors usually improve both firearm accuracy and shooter accuracy. The suppressor on a rifle tends to act as a harmonic dampener and reduce the vibrations of a rifle barrel. For the shooter, the suppressor reduces recoil and muzzle rise. Since the rifle is also much quieter, most shooters will score better with a suppressor. Muzzle flash from unburned powder is reduced or eliminated with a proper suppressor.

How do suppressors work, is another common question. Suppressors work like a muffler on a lawnmower, car, motorcycle, or any other device that discharges large amounts of gas rapidly or repeatedly. The whole idea of a suppressor or muffler is to delay, confuse, diffuse, and cool the gas being exhausted.

When a firearm is discharged, the expanding – and usually still burning -- gases behind the bullet are moving much faster than the bullet itself. Temperature upwards of 2500 degrees Fahrenheit, and velocities above 5000 feet per second are not uncommon. This combination accounts for the bang, the flash, and a substantial amount of the recoil when the gases exit the firearm as a coherent, concentrated jet.

The whole idea of a suppressor is to delay the gas, by making it travel much further than it would on its normal path out of the barrel. Forcing the hot gases to be diverted away from the bore, and making them collide with other parts of the jet seeking escape confuse the jet as it tries to find its way out of the maze we call a suppressor. During this delay, the gases cool and further reduce the volume that actually has to eventually reach outside. Most suppressors can enhance the cooling process and sound reduction by having a small amount of practically any liquid added to the inside of the suppressor. Water, shaving cream, lithium or other grease, and many other substances are used to make a suppressor “wet.”

Once you decide that a suppressor will make your shooting more enjoyable, or you just decide to do your part to prevent noise pollution, there are many types of suppressors and mounts to choose from. There is really no one size fits all model, although there are some suppressors that can be used on different firearms. One side effect of suppressors is that the point of impact changes with a suppressor. So once a firearm is sighted in with a suppressor, most users leave them in place.

There are literally hundreds of models of suppressors from which to choose. Prices range from around $200 to over $2000 for custom “cans” – slang for suppressors -- and mounts. Some suppressors are all aluminum or use carbon fiber outer tubes to keep weight to a minimum. Others use materials as exotic as titanium and are engineered using high tech designs and sophisticated machinery in the manufacturing process.

However, they all have one purpose, whether high tech or simple, reducing muzzle blast to tolerable levels. While it is tempting to just compare dB levels to find the quietest suppressor, many suppressor manufacturers do not publish the measured sound pressure levels, maintaining, more or less correctly, that the measured sound levels is less important to the end user than the perceived sound levels. The muzzle blast is not just a single frequency or tone, but rather a complex combination of different frequencies that varies somewhat from firearm to firearm and even from cartridge to cartridge.

Actual suppressed sound levels – or at least the published numbers – vary, but suppression levels of 20 – 30 dB are in the ball park. This means that a .22 rifle can get down to about 100 dB, and center fire pistols and rifles to between 130 and 140 dB. Please bear in mind that these numbers are not exact and there are a lot of variables to consider. The person considering a suppressor purchase should do a lot of research and find a “Class III” dealer to guide their search for the optimal suppressor for a particular use. Most dealers in NFA firearms are happy to demo suppressors for customers. (This writer loves to stop whatever he is doing to show off suppressors and most other dealers still get a kick out of showing a customer a quiet firearm.)

“I thought silencers were illegal” is a common remark made by people as they encounter a suppressor for the first time. Suppressors are legal in all but a handful of states. However, suppressors are tightly regulated by the Bureau of Alcohol, Tobacco, Firearms, and Explosives. It is even legal in the states that allow suppressors for a person to build their own suppressor. Anyone who can legally own a firearm, can own ANY NFA firearm. However, there are certain hoops to jump through in order to comply with the laws, rules, and regulations.

If a person decides to build their own suppressor or firearm, they must submit a Form 1 along with the $200 tax fee and get the tax stamp BEFORE they can build the device. The form asks a few questions about the proposed design, and use and, generally, unless the builder is a corporation or has what is called an NFA Trust, the chief law enforcement officer must sign off on the form. Then along with the form, you send two “passport photos,” two sets of fingerprints, a check for $200 and wait. How long? The wait can be several months.

Purchasing a suppressor or other NFA firearm requires a different form, but the process is the same – send in the packet and wait. Is it worth the wait? A growing number of shooters believe so. For many jaded shooters, using a suppressor adds a whole new level of fun and comfort to shooting sports.