A gunshot with a silencer (more accurately called a suppressor) typically registers between 130 and 140 decibels, depending on the caliber and ammunition. That’s roughly 25 to 40 decibels quieter than an unsuppressed gunshot, but still about as loud as a jackhammer or the threshold where sound begins to cause pain. The Hollywood portrayal of a near-silent “pfft” is pure fiction.
Suppressed Decibel Levels by Caliber
The amount of noise reduction depends heavily on the firearm and cartridge. A 9mm pistol like a Glock 17 produces about 162 dB unsuppressed. With a quality suppressor, that drops to around 124 dB, a reduction of roughly 38 dB. A 5.56 NATO/.223 Remington AR-15 with a 16-inch barrel runs about 165 dB unsuppressed and drops to around 136 dB suppressed, a reduction of about 29 dB.
At the quieter end of the spectrum, a .22 LR rifle paired with subsonic ammunition and a good suppressor can get remarkably low. Testing by Target Barn measured a suppressed Ruger 10/22 firing Aguila Subsonic rounds at just under 110 dB. That’s comparable to a power tool or a loud concert, genuinely quiet by firearm standards, but still far from silent.
Larger rifle calibers like .308 Winchester are harder to suppress effectively. Even top-tier suppressors on a .308 bolt-action rifle leave the shot well above hearing-safe levels with standard ammunition. The more powder a cartridge burns, the more gas the suppressor has to manage, and there are physical limits to how much sound it can absorb.
Why Suppressors Can’t Make a Gun Silent
The bulk of a gunshot’s noise comes from extremely high-pressure gas decompressing into the atmosphere the instant a bullet leaves the barrel. These gases are traveling at supersonic speeds and are scalding hot, both of which amplify the sound. A suppressor contains a series of internal baffles and expansion chambers that trap and slow these gases, letting them cool and lose pressure before they escape into the open air. This is the same basic principle as a car muffler.
That process can cut up to about 40 decibels from the report. But the suppressor can only address the gas expansion noise. If the bullet itself is traveling faster than the speed of sound (roughly 1,125 feet per second at sea level), it produces a supersonic crack that the suppressor does nothing to reduce. This is a separate, sharp sound that follows the bullet’s path and is clearly audible to anyone nearby.
Subsonic Ammunition Makes a Real Difference
To eliminate that supersonic crack, shooters use subsonic ammunition, which keeps the bullet below the speed of sound. Combining subsonic ammo with a suppressor reduces the overall noise level more than either one achieves alone. The suppressor handles the muzzle blast, and the slower bullet eliminates the crack.
The tradeoff is performance. Subsonic rounds carry less energy and drop more over distance, which limits their effective range. This is why suppressed .22 LR and 9mm setups with subsonic loads tend to be the quietest practical combinations, while suppressed rifle cartridges like 5.56 NATO are still quite loud since most factory loads are supersonic.
Wet Suppressors and Extra Noise Reduction
Some suppressors can be run “wet,” meaning a small amount of water, wire-pulling gel, or another ablative medium is added to the interior before firing. The liquid absorbs additional heat from the expanding gases, cooling them faster and reducing noise by an extra 3 to 10 decibels compared to the same suppressor run dry. The effect is temporary, usually lasting only a few shots before the liquid evaporates, but it represents the lowest sound levels a given setup can achieve.
How Loud Is “Loud” in Context
Decibels are measured on a logarithmic scale, which means small numbers represent big real-world differences. A 10 dB reduction cuts perceived loudness roughly in half. A 30 dB reduction means the sound feels about one-eighth as loud. So a suppressed 9mm at 124 dB genuinely sounds dramatically quieter than the 162 dB unsuppressed version, even though 124 dB is still extremely loud by everyday standards.
For context, OSHA sets 140 dB as the threshold for immediate hearing damage from a single impulse noise like a gunshot. An unsuppressed firearm exceeds that limit with every shot. A suppressed 9mm at 124 dB falls below that threshold, which is the primary practical benefit of suppressors: hearing protection. A suppressed AR-15 at 136 dB is still below the danger line but closer to it. Suppressed .22 LR setups around 110 dB are comparable to attending a loud concert without earplugs.
Even at the quieter end, a suppressed gunshot is nothing like what movies suggest. At 110 to 136 dB, the sound is clearly recognizable as a gunshot to anyone within a reasonable distance. It’s quieter, less startling, and far less damaging to your hearing, but it is not subtle. The most accurate way to think about a suppressor is as a muffler, not a silencer. It takes a dangerously loud explosion and makes it merely very loud.