Suppressors for Hunters — What You Need to Know

There is an informative article on the NRA’s American Hunter website regarding suppressor use for hunting. The article, What Hunters Need to Know About Suppressors, answers common questions about licensing, tax stamps, and suppressor types. The article explains the history of the $200 tax stamp which must be paid when acquiring a suppressor:

“Why the Tax? In 1934 … the federal government, while battling gangsters such as Al Capone, heavily restricted silencers with passage of the first National Firearms Act. Hoping to gain an advantage on criminals that often had better weapons than cops, the Feds placed a mandatory ‘sin’ tax on silencers that was so high it would effectively ban their purchase by all but the wealthiest individuals. In 1934, $200 was the equivalent of $3,500 today. The $200 tax still stands despite no evidence that a simple metal tube is capable of causing crime.” — American Hunter

The American Hunter article also discusses how well suppressors actually reduce noise. User should be aware that the sound level of a large, centerfire hunting cartridge will still exceed 130 decibels (dB) on average, even with a typical suppressor (silencer) in place. For that reason, we recommend that hunters continue to wear ear protection even when they shoot suppressed.

For example, Thunder Beast Arms says its latest Ultra 9 Suppressor will reduce the report of a .308 Win to 132-134 dB: “The ULTRA 9 will suppress a typical .308 bolt-action rifle down to approx. 132-134 dB. It also has very little or no ‘first round pop’ (FRP) in most applications.” NOTE: These dB levels are measured in accordance with MIL-STD-1474D using BK 2209 SLM offset one meter from muzzle.

How Loud Are Unsuppressed Rifles?
Firearms Are Loud — 140 dB to 175 dB. Audiology group ASHA explains: “Almost all firearms create noise that is over the 140-dB level. Exposure to noise greater than 140 dB can permanently damage hearing. A small .22-caliber rifle can produce noise around 140 dB, while big-bore rifles and pistols can produce sound over 175 dB. Firing guns in a place where sounds can reverberate, or bounce off walls and other structures, can make noises louder and increase the risk of hearing loss. Also, adding muzzle brakes or other modifications can make the firearm louder. People who do not wear hearing protection while shooting can suffer a severe hearing loss with as little as one shot[.] Audiologists see this often, especially during hunting season when hunters and bystanders may be exposed to rapid fire from big-bore rifles, shotguns, or pistols.” Source: ASHA, Recreational Firearm Noise Exposure.

How Much Does a Good Suppressor Really Reduce Firearm Sound Levels?
That depends on the rifle, the cartridge, and the effectiveness of the suppressor. The American Hunter article explains: “Suppressors retard the speed of propellant gases from the cartridge that rapidly expand and rush out of the barrel. It’s these gases that produce the loud boom that’s heard for miles. A suppressor’s series of internal baffles slows these gases so they are not all released at once, thereby muffling the sound.” Many good commercial suppressors can achieve 30-35 dB sound suppression. However, Zak Smith of Thunder Beast Arms says: “There are a bunch of manufacturers who publish values that are not reproducible, or use an ad-hoc test instead of a mil-spec test. In many cases we’ve tested the exact same suppressors they’ve advertised with 30-40 dB reductions and found they are actually in the high 20s instead.”

Again, for this reason, we recommend that hunters use ear protection, such as electronic muffs, even when shooting suppressed.

Choosing a Suppressor for Hunting Use
The American Hunter article explains that there are many types of suppressors on the market. Bigger suppressors are heavier, but they normally are more effective. You also have a choice in muzzle attachments:

“For most hunting applications, direct thread is the best choice. If you intend to buy only one suppressor yet you have multiple guns, it’s advantageous to buy a model sized and rated for the largest caliber you intend to use. While a suppressor made specifically for a .223 Rem. will reduce the sound of that round slightly better than a model made for .30 caliber, for example, you can use a .30-caliber can for smaller calibers — but not vice-versa. In general, the bigger the can, the more it reduces sound. Smaller suppressors, however, are easier to carry in the woods.” — American Hunter

Chart from American Suppressor Association.

How to Apply for a Suppressor
To acquire a quality suppressor, you’ll first need to shop around, comparing verified performance. Unfortunately some manufacturer’s dB claims are exaggerated. Give due consideration to size, weight, and durability. When you’ve selected a brand and model, find a Class 3 dealer authorized by the ATF to sell suppressors. You must fill out ATF Form 4, get fingerprinted, and pass a background check. Along with two completed copies of Form 4, submit your fingerprint card, passport photo and a check for $200 to the ATF. Then you wait for the ATF to process your application. American Hunter says the average ATF suppressor processing wait time is now nine months.

BENEFITS OF SILENCERS

NOISE REDUCTION
According to OSHA, the threshold for a hearing safe impulse noise is 140 dB. Without hearing protection, exposure to any impulse noise over 140dB causes varying degrees of permanent noise-induced hearing loss, which can also lead to tinnitus. Most well-engineered silencers take the dB level of their host firearm well below 140 dB, making those silencers effective primary hearing safety devices. You should always still wear hearing protection (muffs or plugs) when using suppressors.

RECOIL REDUCTION
By containing the explosion at the muzzle, suppressors significantly reduce perceived recoil energy, reduce the rifle’s rearward movement on recoil, and reduce rifle torquing and muzzle flip. The reduction of recoil (and rifle torquing/hopping) lessens shooter fatigue and helps the shooter get his sight picture back on target rapidly after firing. With smaller calibers, a suppressor may enable the shooter to maintain a nearly-continuous sight picture, following the shot into the target. In addition, by reducing felt recoil (and muzzle blast), a suppressor can help inexperienced shooters avoid flinching.