Benefits of Shooting With a Sound Suppressor

In a post-meltdown survival situation, the use of sound suppressors or gun “silencers” will offer several advantages for hunters and territorial defenders. In this article we will examine two popular suppressors by Yankee Hill Machine and do a noise comparison. Although the technical name of these devices is sound suppressor, the term silencer, while inaccurate, is still used in the US code and regulations, and in common parlance among many competitive and recreational shooters. Nomenclature snobs be warned: I’ll use the terms suppressor and silencer interchangeably.

As far as I know, it is illegal in every state to hunt with a silencer, ostensibly because it makes it easier to poach. Even if you’re not poaching, it’s still illegal. I think it’s silly, but I comply and I’m not recommending to anyone that they break the law. That said, in a life or death survival situation, a silencer definitely gives the hunter or territorial defender some advantages:

• First, by suppressing the sound of the blast, it reduces the area in which game and hostile persons will be alerted to his presence. For the hunter, this significantly increases the ROI of energy expenditure, as he has to travel lesser distances to find game. Over a long winter, this could well mean the difference between survival and starvation.
• Second, by suppressing the blast, it makes it more difficult to localize the shooter. While the sonic crack of the flying bullet is not suppressed, it is not a localized event, but a more generalized sound that does not offer pinpoint data about the shooter’s position. (The sonic crack is just a miniature sonic “boom,” whose sound is perceived in relation to the observer’s location in the bullet’s mach cone angle, which varies by the bullet’s shape, velocity, and height above the observer, not in relation to the bullet’s point of origin. That’s a lot of variables, and the point is, the sonic crack of the bullet doesn’t give the observer much useful information about its point of origin. If you’d like to drill deep into the physics of the mach cone, read about the Prandtl-Meyer Expansion Fan). It’s not perfect — there is still an audible blast, and even the mechanical signature of the gun is detectable for some distances, sometimes great distances, as when shooting near a body of water.
• Third, the silencer is an extremely effective flash suppressor, which allows the shooter to operate in twilight or dark conditions without revealing his position.
• And finally… the first three advantages are tactical; this one is practical and applies in any situation. The simple fact of reducing noise helps prevent hearing damage and abates possible nuisance to neighbors who don’t like to hear frequent gunshots.

Silencers are class III items under the National Firearms Act, so they have to be registered with the federal government. Registration costs $200 per silencer, and must be administered by a properly licensed firearms dealer. If you want one, find your friendly neighborhood class III dealer and get started soon because it can take several months for the paperwork to clear.

If there’s any disadvantage to using a silencer, it’s that it creates a lot of blowback. Eye protection is good practice any time you shoot, but with a silencer it’s mandatory. Blowback is especially bad when shooting a suppressed semi-auto rifle because your face is so close to the firing mechanism, and your eyes get a concentrated dose of blast gases. You can hold your breath and avoid breathing the noxious fumes, but you can’t really close your eyes while shooting, can you? After a few magazines my face looks peppered with oil and dust, and my glasses have to be cleaned.

Sound suppressor comparison video

In this video we compare the sound of a .223 caliber round shot through a suppressed and unsuppressed Colt 5.56 Carbine. Using the same gun, we also compare the sound of a .22 LR round shot with and without the Phantom suppressor. The CMMG .22 conversion kit replaces the firing bolt and allows the use of .22 LR in an AR 15. With the suppressor mounted, the conversion kit failed to feed, and I was only able to demonstrate single shots. I haven’t yet determined what was causing the FTFs.

You can also see the dramatic effect of the Mite on the Walther P22. Because the .22 round is subsonic when fired from the P22, the amount of suppression is remarkable, even without water.

Examining the Yankee Hill Machine Phantom 5.56

Here we have a YHM Phantom for the 5.56 mm round. As you probably know, 5.56 is the same diameter as .223 caliber, and can be used with either round. It can also be mounted on a .22 rifle or, as I did here, on an AR 15 with a .22 conversion kit. This allows you to shoot .22 cartridges from your AR 15. In our demonstration, the Phantom was mounted on a Colt 5.56 Carbine with the QD mount/flash hider.

The Phantom has some very appealing design features. This particular model comes with a QD (quick detach) mount that allows rapid attachment and detachment from the barrel (some models are threaded directly to the barrel of the gun). The QD mount doubles as an effective flash hider when the sound suppressor is not mounted. When mounted, a gas seal keeps the threads clean so they won’t bind, making it much easier to remove the suppressor by hand. The flash hider is not merely a convenience — it is designed to support the suppressor on two concentric thread coils. This important safety feature helps keep the suppressor on axis even if not fully tightened, which helps avoid dangerous and expensive baffle strikes.

YHM QD Phantom 5.56 Specifications

• Caliber — .223 cal/5.56 mm
• Length — 6.875 in
• Diameter — 1.500 in
• Weight — 20 oz
• Suppression Level — -35 dB
• Material — Chrome moly steel and heat treated Inconel 718
• Finish — Matte Black
• Retail cost — $565 (plus the $200 federal registration fee)

The YHM .22 Mite

One of the most interesting aspects of the Mite is that it can be disassembled for cleaning, and comes with a disassembly tool for easy service. The small diameter of this silencer allows the use of stock sights, in most cases — some other silencers are so big around that you have to mount raised sights in order to see over the can. This can weighs in at under 3 ounces; amazing considering what it delivers in terms of sound suppression.

Don’t let Hollywood set your expectations, but depending on caliber, pistol silencers can have a remarkable effect. If you shoot a .45 or a .22 pistol, both of which are subsonic, the amount of sound suppression is truly impressive because there’s no sonic crack of the bullet to spoil the effect. In fact, you’ll find the gun’s mechanical cycling clearly audible. This is not to say that your gun will sound like the Hollywood “dzip” or “phut,” but I can shoot the Mite all day without hearing protection, and I really think my little girl is louder when she greets me after work.

YHM .22 Mite Specifications

• Caliber — .22
• Length — 5.300 Inches
• Diameter — 1.00 Inches
• Weight — 2.9 Ounces
• Suppression Level — -35 to -40 dB Depending on Host Firearm
• Material — Aircraft Quality Aluminum and Stainless Steel
• Finish — Matte Black Hardcoat
• Method of Attachment — 1/2″-28 Threads
• Retail cost — $283 (plus the $200 federal registration fee)

Using water to improve sound suppression

Sound suppression is enhanced by the use of water in the can. By vaporizing and atomizing, water absorbs energy that would otherwise go into blast noise and flash. Grease and oil can also be used, but water is much more effective because it has a much higher specific heat. In other words, for a given mass, it takes a lot more heat to raise the temperature of water than it does oil or grease, so a gram of water will attenuate more energy than a gram of oil or grease. Another disadvantage is that grease and oil are messier than water, which is already bad enough. Water-based gels are also effective, but care must be taken to clear the bore before firing, or dangerously high pressures may develop.

I don’t recommend the use of water, gels, oil, or grease in rifle suppressors because the pressures involved are so much greater, and I’d be concerned that it might damage the suppressor, creating a potentially dangerous situation for the next shot. In any event, there’s so much energy in rifle shots that wet suppressors are only effective for one or two shots at a time.

OPSEC and suppressor registration

I concede that registering your suppressor is incompatible with operational security. Any time the state decides to confiscate suppressors, it will know you have yours, as you can’t legally transfer it without registering the transfer. But it is conceivable that in a post-meltdown scenario, individual liberties might actually improve, and that the state would refrain from confiscating guns and NFA items like suppressors. In that case, you’ll be able to reap the logistical and tactical benefits of owning a silencer.

And if that’s not the case, and you lose your suppressor, at least you will have had some fun with it.

~ SnoMan