The short answer is that all guns are loud. Anything starting from a .22 Long Rifle produces enough noise to cause permanent hearing damage. Today, we are going to specifically look at some of the loudest guns and the noise levels they generate.
What is the average noise level of a gunshot?
Shooting guns is an inherently dangerous activity. For this reason, we put safety protocols into place, like the Four Firearms Safety Rules. Another safety control measure that is put in place is the proper use of personal protective equipment (PPE). Firearms almost always exceed hearing-safe levels. Noise exposure as low as 85 decibels can cause damage to human hearing and the average noise level of a gunshot is between 140 and 160 decibels. Even suppressed firearms can routinely reach 140 decibels, though most attempt to keep noises below the 140 line.
Let’s take a look at some specific firearms and talk about which ones produce the most noise in decibel levels…
Which Gun Has the Quietest Sound?
With the ever-increasing popularity of suppressors, some guns are quieter than ever. The award for quietest ever, though, goes to the DeLisle Carbine produced during WWII. It was one of the quietest firearms ever made and featured an integral suppressor. It was a bolt-action, which eliminated cycling noise upon firing, and it fired the subsonic .45 ACP cartridge.
What is the Loudest Gun?
The loudest recorded gun is the .50 Browning Machine Gun (BMG). The big .50-caliber is renowned to produce noise levels of 180 decibels. This is as loud as a rocket launching, and hearing loss when exposed to this is inevitable.
But, answering this question of “What is the loudest gun?” isn’t perfectly straightforward. Writers often use terms like “all things being equal,” but all things are rarely equal. Here’s what we mean: a rifle places the gunshot noise further from the shooter’s ear, lessening the impact on the shooter. A pistol, on the other hand, places the noise closer to the shooter, making it significantly louder. Therefore, they are not necessarily equal. Additionally, shooting the same gun indoors vs. outdoors will change the perceived level of noise, and therefore could potentially change the level of exposure. There are a variety of factors that can impact the noise levels experienced by the shooter.
Additionally, there is a big difference between a .22 rifle and a .22 pistol or revolver. For example, a Ruger 10/22 rifle produces about 140 decibels of noise. This is right at the threshold that OSHA defines as “exposure to impulsive or impact noise.” But, a Walther .22 pistol generates significantly more noise, emitting 157 decibels, a 17-decibel increase. And keep in mind that sound is not additive, it is logarithmic, meaning the .22 pistol is many, many times louder than the rifle. All of this is important to keep in mind as we go through these cartridges, from quietest to loudest.
How Loud are Pistols?
All centerfire pistols and revolvers are loud. The lowly 9mm Luger fired from a Glock 17, for instance, can produce 159.8 decibels. A .45 ACP cartridge fired from a 1911 pistol can generate up to 165 decibels. Both of these are loud enough to cause immediate hearing damage.
Large-Bore Revolvers?
The big-bore revolvers: the .44 Magnum, .454 Casull, .460 S&W, and the like can produce some seriously high decibel levels. The loudest in its class, the .500 S&W has reportedly produced up to 166 decibels, louder than some rifles, as we will see.
Shotguns?
Shotguns can also produce a tremendous amount of noise. The larger bores including 12 gauge are the loudest. A 12-gauge, 3 ½” Magnum can generate 161.5 decibels. This is on par with rifles.
Rifles?
Rifles are loud due to their high power and high velocity. Generally speaking, the more powerful the rifle is, the louder it will be. The .45-70 caliber rifle can produce 160.1 dB, the .270 Winchester can generate 161.9, the .30-06 Springfield 163.6, and the 7mm Remington Magnum a whopping 166.5. These are extremely loud noises and will damage hearing permanently.
How Far Away Can a Gun Be Heard?
Guns can be heard for quite long distances. If you are lost in the woods this is sometimes recommended as a signaling technique to lead rescuers to your position. But how far can a gun be heard? There are a lot of factors involved in this one, too, including the type of gun, the terrain, and even the weather or temperature. A gun fired in a dense forest won’t be heard as far away as a gun fired on open plains. Additionally, sound travels faster when temperatures are lower.
In ideal conditions, a handgun shot can be heard for a mile or more. Significantly louder firearms, like shotguns and rifles, can be heard from double that distance. Suppressed firearms will be heard for shorter distances since the noise levels are reduced. A suppressed, subsonic cartridge may only be heard from 25-50 meters away.
What Affects the Noise of a Gun?
Numerous factors make one gun louder or quieter than others. The environment can greatly affect the perceived noise. Being outdoors on a cloudless day can make guns seem much less noisy than shooting at the same place with low cloud cover, and certainly quieter than shooting indoors. Another factor is location, as mentioned earlier, and when there is a surface (or surfaces) for noise to reverberate, the gun will be louder. This can be the walls, floor, and ceiling of an indoor range. It could also be terrain in a box canyon or similar environment. Even low, heavy cloud cover can make noises seem to be louder.
What parts affect the noise of a gun?
Cartridges
There are some factors inherent to the cartridge that influence how loud or quiet it is. First, the speed of the bullet is a big factor. After the bullet exceeds 1,100 feet per second it will break the sound barrier, emitting a supersonic “crack” which generates additional noise. Additionally, the more powder that is ignited when the gun is fired, the louder it will be. Once the bullet leaves the muzzle, all of the gasses behind it escape, resulting in a loud “boom” known as the muzzle blast. This, coupled with the supersonic crack create the noise of the gun. Finally, the larger the bore, the louder the gun will be.
Form Factor
Pistols are frequently louder than rifles. This is because the muzzle of a pistol is generally closer to the shooter’s ear than a rifle’s muzzle. This is also the case when considering short-barreled rifles versus longer-barreled rifles of the same caliber. But that’s not all there is to the story. Pistols have shorter barrels than rifles. As such, they tend to utilize faster-burning powders to ensure the powder is mainly consumed by the time the bullet exits the barrel. This creates higher pressure and a louder bang.
Impact Noise
Another factor is the impact noise of the bullet striking its intended target. If you are shooting in the desert and the bullet impacts miles away, this is probably not an issue. If, however, you are shooting at steel targets, tremendous noise is created on impact, sometimes reaching 140 dB. Impact noise is typically overlooked because it is not as loud as the gunshot but if you shoot with a suppressor, however, impact noise will suddenly become very apparent.
Modifications
Modifications made to the gun can also make it louder. Just as suppressors and silencers can make a gun quieter, muzzle brakes can make it louder. Muzzle brakes redirect escaping gasses back toward the shooter to keep the muzzle rise down or to help control recoil. In handguns, this is sometimes known as a compensator, or sometimes the barrel itself will be ported to achieve the same ends. Unfortunately, this puts escaping gas even closer to the shooter’s ear, making it seem louder. It can even create a teeth-rattling, concussive experience.
Why do guns have different sounds?
Many firearms have different sounds. Famously, the AK-47 and M16/M4 have very different sounds. The M16/M4 has a much sharper “crack” than the AK, which produces a very distinctive booming sound. Most hunters can differentiate between a 12-gauge shotgun and a high-powered rifle round being fired some distance away. Again, the shotgun has a very deep, resonant “boom” while the rifle has a much sharper crack, likely due in part to the sonic boom as the bullet passes the sound barrier.
The barrel length also changes how the shot sounds. The longer the barrel, the faster the velocity of the bullet, but (all things being equal) the less muzzle blast, resulting in a sound with more crack than boom. The shotgun pellets don’t create the same supersonic “crack” as a bullet.
How Do You Protect Your Hearing While Shooting?
Well, with hearing protection. Now that you know just how loud guns are, you know how crucial it is to protect your hearing while shooting. With some of the most protective models on the market, Pro Ears can significantly reduce damage to your ears. We carry a variety of hearing protection models with a high noise reduction rating (NRR) to protect your hearing. Explore our hearing protection here!