Contrary to popular portrayal in action movies and video games, suppressors (often incorrectly called “silencers”) do not completely eliminate the sound of a gunshot.
Instead, they typically reduce the sound level by 20-40 decibels, depending on various factors, including the firearm type, ammunition, and suppressor design. This reduction is significant—comparable to the difference between standing next to a jackhammer and the noise of a busy restaurant—but far from the whisper-quiet “pfft” often depicted in entertainment media.
A suppressed centerfire rifle often still registers above 130 decibels, which exceeds the human pain threshold of 120 decibels, and remains louder than a leaf blower at close range.
Understanding Sound Measurement
When discussing suppressor performance, we’re dealing with decibels (dB) – a logarithmic unit that measures sound intensity. Here’s where things get interesting: the logarithmic scale means that human ears perceive a reduction of 10 dB as roughly half as loud. Decibels (dB) is the “raw” measure of sound, whereas dBA takes into account human perception.
For reference, normal conversation typically registers around 60 dB, while a lawn mower operates at approximately 90 dB. An unsuppressed firearm can generate between 140-175 dB, well above the 140 dB threshold where immediate damage to unprotected hearing can occur. Modern suppressors typically reduce this by 25 to 35 dB, bringing the sound levels down to a more manageable range that sounds more like a .22 LR rifle, though still not “Hollywood quiet.” This is why hearing protection is still essential for range sessions, even when using suppressors.
The Science Behind Suppressors
Suppressors capture and slow the high-pressure gases that exit the barrel when a round is fired. These expanding gases create the loud report associated with gunfire. A typical suppressor consists of a series of internal chambers separated by baffles.
As the propellant gases enter the suppressor, they expand into these chambers and cool slightly before exiting the muzzle. This process significantly reduces the pressure and velocity of the gases, resulting in a less intense sound wave.
Think of it as the difference between popping a balloon with a pin versus slowly releasing the air—the end result is the same (deflated balloon), but the sound intensity differs dramatically.
Factors Affecting Sound Reduction
Multiple variables determine exactly how much sound a suppressor will reduce. The caliber and type of firearm play a significant role, with larger calibers generally being more difficult to suppress effectively.
For example, a suppressor might reduce a .22LR rifle’s report by 40 dB, bringing it down to around 115 dB, while the same suppressor might only reduce a .308 rifle’s report by 25 dB, leaving it at around 140 dB.
Additionally, the ammunition itself matters tremendously. Subsonic ammunition, which travels slower than the speed of sound (approximately 1,100 feet per second at sea level), eliminates the sonic crack produced when a bullet breaks the sound barrier, resulting in much quieter shots when paired with a suppressor.
Suppressor Types and Their Effectiveness
Not all suppressors are created equal. Modern suppressors vary widely in design, materials, and effectiveness. Multi-caliber suppressors offer versatility but may not provide optimal sound reduction for each individual caliber.
Purpose-built suppressors designed specifically for a particular firearm and caliber typically offer better performance. Longer suppressors also typically suppress more sound, but new design innovations are making compact suppressors surprisingly effective.
Material construction also affects durability and sound reduction. Titanium suppressors provide an excellent balance of durability and lightweight but can be more expensive, while stainless steel options offer durability at the cost of added weight. Some high-end suppressors utilize advanced materials like Inconel for high-temperature resistance in rapid-fire scenarios, potentially maintaining better sound reduction during extended use.
Real-World Decibel Reduction Examples
To put suppressor effectiveness into perspective, consider these typical examples. An unsuppressed 9mm handgun produces approximately 160 dB of sound. With a quality suppressor, this can be reduced to around 125-135 dB—a significant reduction, but still louder than a chainsaw (110 dB) and substantially louder than Hollywood would have viewers believe.
For a .223/5.56 rifle commonly used in AR-15 platforms, the unsuppressed sound reaches about 165 dB, while a suppressed shot might register around 135-145 dB. The most dramatic reductions occur with subsonic .22LR ammunition, where a suppressed firearm might produce shots as quiet as 115-120 dB, roughly equivalent to the sound of a pellet gun at close range.
Understanding Manufacturer Ratings
Suppressor manufacturers often advertise their decibel reduction ratings under specific test conditions, but these numbers don’t tell the whole story. I’ve found that real-world performance can vary significantly based on multiple factors.
For instance, a suppressor rated for 32 dB reduction on a .308 bolt action might only achieve 27-28 dB reduction on a semi-automatic platform due to additional port noise. This isn’t marketing deception – it’s simply the reality of how different firearms and ammunition interact with suppressor technology.
First-Round Pop Phenomenon
Serious suppressor users often discuss the “first-round pop” (FRP) phenomenon. When a suppressor is first used after sitting unused, oxygen remains inside the suppressor. When the first shot is fired, this oxygen combines with the propellant gases and creates a secondary combustion, making the first shot noticeably louder than subsequent shots.
After the first round, the suppressor fills with inert gases, eliminating this effect for following shots. This phenomenon can add 5-10 dB to the first shot, which is why sound testing protocols typically measure after the first few rounds have been fired.
Practical Applications and Considerations
In real-world applications, absolute decibel reduction isn’t always the most important factor. Having run suppressors in various tactical and hunting scenarios, I’ve found that tone and sound signature often matter more than raw decibel numbers.
A suppressor that achieves slightly less decibel reduction but produces a less distinctive sound might be preferable for certain hunting applications.
Additionally, factors like point of impact shift, added length and weight should be considered alongside sound reduction when selecting a suppressor. I prefer a shorter and lighter suppressor for hunting, knowing that I’m sacrificing a little less decibel reduction.
Wrapping Up
Understanding suppressor decibel ratings requires considering multiple factors beyond the simple numbers provided by manufacturers.
While technical specifications provide a useful starting point, real-world performance depends on a combination of factors including firearm platform, ammunition selection, environmental conditions and practical application requirements.
As suppressor technology continues to advance, staying informed about these various aspects will help shooters make better decisions about their suppressor selection and expectations.
More than a bit curious how a 32acp in a larger format (Beretta 8x or larger) would fare. Ah well another decade I guess.
As before when I pointed this out:
“When discussing suppressor performance, we’re dealing with decibels (dB) – a logarithmic unit that measures sound intensity. Here’s where things get interesting: the logarithmic scale means that human ears perceive a reduction of 10 dB as roughly half as loud. Decibels (dB) is the “raw” measure of sound, whereas dBA takes into account human perception.”
No
Corrected: ‘…human ears perceive a reduction of 10 dBA as roughly half as loud. ….
If you were measuring – half would be 3dB
If you are perceiving it – half is (roughly) 10 dBA
“logarithmic scale means that human ears perceive a reduction”
No. The logarithmic scale has nothing to do with how, or why, the “human ears perceive a reduction”. It has to do with how the brain interprets the sound energy as perceived by our ears – this is the ‘perceive’ portion. We determine that level of perception in dBA, which means A-weighted decibels which is an expression (not measurement) of the relative loudness of sounds as perceived by the human ear. You can’t measure sound energy ‘perception’ as an absolute because perception varies from person to person, but you can measure raw (dB) and then relate that to the logarithmic scale as an expression of dBA based upon an average.
Correction for: “…as an expression of dBA based upon an average.”
Should have been…
… as an expression of dBA based upon an average (or other ‘foundational’ expression calculation or means – depending on the specific application).
dBA is an expression formed in calculation.
Human ears detect “weighted” sound levels. Our brains translate that detected by the ears for a sense of the sound level, or in other words ‘perception’. Human ears ‘detect’ “weighted” sound levels because our ears do not treat all frequencies the same, and not all humans perceive sound levels the same. We perceive some frequencies as being louder (or less loud) than others because our ears do not have a very ‘flat’ frequency response. To accommodate this, to get an idea of a value we can assign to this perception, there are several different algorithms of decibel weightings that we call ‘scales’.
The scale most frequently used, and associated for ‘suppressor’, is the A-weighted scale. The values on this scale are expressed in dBA (the A stands for A-weighted). dBA is a calculated value and not a measured value, thus we can’t apply a logarithmic measurement and need a ‘foundational’ expression calculation or means to relate it to other ‘units’ (i.e. dB) that are not A-weighted.
‘Perceived’ sound levels are how our ears and brain interpret the sound. In other words, perception answers the question of “What sounds ‘twice as loud’ or ‘half as loud’?”
For example:
a 3dBA increase in sound level is barley detectable to the human ear, over 80% of adults can’t detect it and of the ones who can its more of a ‘warm fuzzy barely a sense’ of the increase (or decrease) in sound level and if you are able to have that if you don’t pay close attention and concentrate that barest hint of perception is gone as if it was never there. Its not until you get to 5dBA that one begins to actually perceive a sound level change. At 10dBA the perception of the sound level is that it has roughly doubled (or roughly half as loud for decrease).
3dBA is tiny – and its not a measurement on the logarithmic scale.
3dB is a big change – it is a measurement on the logarithmic scale.
For example, for a simple comparison:
Say you make $100,000.00 a year and you gave me 3bB of it. You would be giving me $50,000.00.
Say you make $100,000.00 a year and you gave me 3bBA of it. You would be giving me less than a penny.
When we are talking about dB we are we talking about measurable ‘physical’ sound level energy (AKA sound level pressure). When we are talking about dBA we are talking about perception, which we can’t measure, its “What sounds ‘twice as loud’ or ‘half as loud’?”, the relative ‘sense’ of that which we perceive. There is a big difference between dB and dBA.
Sounds sounds like they don’t work all that great for the price and permissions.
Sounds sounds like stuffing cigarette butts in your ears works just as well.
Ohhh fck me running, Cigarettes are controlled by the ATF too.
There is no hope.
Can always drink your sorrows away………..
Explosives make me smile.
Beware of dog
Xdduly,
I purchased a suppressor last summer and installed it on a carbine with 16-inch barrel chambered in 9mm Luger. When I shoot sub-sonic ammunition through it, it significantly reduces sound level.
Here is an actual example: I stood outside about 20 feet away from a home and shot a single sub-sonic cartridge through my suppressor into the ground. My father was indoors. One path for the sound to reach him was through two closed sliding-glass doors and straight to his position–or through a closed kitchen window and around a corner to his position. He did not hear the shot. I can assure you that he would have heard the shot if I was not using a suppressor.
Putting this a bit more in perspective, I will shoot one subsonic cartridge without hearing protection. My ears sort of twinge with a hint of ringing for about a half second and the ringing is gone. Without the suppressor, my ears would be ringing for several minutes. (I have pretty sensitive hearing.)
I absolutely HATE the $200 tax stamp and registration process for legally acquiring a suppressor. Adding insult to injury, that process used to take about 12 to 18 months which is why I refused to purchase a suppressor in the past. When government turn-around times dropped to about three weeks, I finally swallowed the proverbial bitter pill (paying the $200 tax stamp and enduring the registration process) and purchased my first suppressor. As much as I hate the process, I LOVE having my suppressor.
My ears been fcked since 72.
I won’t let my grandkids shoot unless they have eye and ear protection.
Hunting is where I see the real advantage to a silencer.
My Doctor Neverinhisofficegonehunting has suppressors on all his hunting rifles.
Sometimes all we can do is improve things a bit for those who come next.
“Putting this a bit more in perspective, I will shoot one subsonic cartridge without hearing protection. My ears sort of twinge with a hint of ringing for about a half second and the ringing is gone. ”
Good example of hearing damage.
If your ears are ringing from the suppressed shot then you do for a fact have hearing damage even if its a “twinge with a hint of ringing for about a half second”.
If your ears are not ringing from the suppressed shot (for above .22 caliber subsonic), its most likely because you already have some form of hearing damage, maybe ever so slight, that dampens the ear frequency response even more and you don’t notice it because your brain has compensated and adapted for perception of sound and has suppressed the ringing.
The reason the ringing went away is because your brain tuned it out, not because there was no damage to the sound-sensing-structure of the ear.
Your example shows the reason that suppressors are not ‘hearing protection’ devices, but rather ‘hearing safety’ devices. There is a big difference between ‘hearing protection’ and ‘hearing safety’. And this thing that suppressors are ‘hearing safe’ we often see from people and manufacturers – there is nothing ‘hearing safe’ about ‘mitigation’, there is only lessening immediate detrimental impact with ‘hearing safe’ and not doing away with immediate detrimental impact (like your ear ringing example shows).
Basically; ‘hearing protection’ prevents – ‘hearing safety’ mitigates. They are not the same thing. For ‘mitigates’ its about ‘lessening immediate detrimental impact’ upon hearing and not doing away with ‘detrimental impact’ upon hearing. For ‘preventing’ its about keeping that ‘immediate impact factor’ from having detrimental effect. Its two different things. Suppressors are not ‘hearing protection’ devices.
For minor hearing damage – the brain does that for minor damage, tunes out the ‘ringing’ (which is really tinnitus) so you don’t notice it. But the damage to the sound-sensing-structure of the ear is still there even if you don’t notice it, and the body over time, if the damage is minor enough, will repair it. But even though the body might repair such minor damage, it will always be a weaker sound-sensing-structure where the body repair was made. Repeated exposure to weapons fire, even suppressed like you did without hearing protection, will continue to hit that weak spot and, or normal body aging and/or other sounds will, further degrade that weak spot over time. Then eventually at some point in your life you will have at a minimum some level of permanent hearing damage tinnitus or some type of hearing loss that may take the form of certain frequency ranges not heard as clearly any longer.
Then there is immediate permanent damage. If the ringing does not go away after no longer being exposed, in say less than a minute but might several minutes later go away or may not go away then you have immediate permanent damage that is not minor and the body will never repair the damage. The brain may somewhat compensate and the total effect of the damage, depending on the person, may not be noticed until some time later, maybe years in some cases, but the damage is still there and is permanent.
Then there is pain. If you feel pain, any level of pain, with the weapons fire, even suppressed, then for a fact you have immediate permanent damage and although it may vary as to the effect overall, your hearing will never be the same again and the body will never repair any of the damage.
You should still wear hearing protection if using a suppressor.
Anyone who tells you that you do not need hearing protection when using a suppressor is, even if they do not realize it, not telling you the truth.
.40 cal Booger,
Thank you for the information.
For reference it was only two times (separated days apart) that I shot a single cartridge through my suppressed carbine without hearing protection. And I only did that because I wanted to know just how effective the suppressor was if I ever had to shoot in self-defense (with the implication that I would not be able to don ear muffs during the self-defense event).
I have always been planning to use ear muffs or ear plugs during any target practice or hunting with a firearm that has a suppressor–for all of the reasons that you stated.
Fun tidbit: during target practice without a suppressor I usually use ear plugs PLUS ear muffs.
“…suppressors (often incorrectly called “silencers”) do not completely eliminate the sound of a gunshot. “
Suppressors most certainly mute gunshots to a level undectable outside the room where the shot happens, or within 10ft of the shot, outdoors. If’n it twernt so, a whole bunch of hollywood people would be in jail for lying to the public, who is paying to see reality in movies; fraud.
Oh yes, photon torpedos do make a sound in galactic space.
(In the ‘Lessons Learned’ department) — SHOCKING: Body cam video shows officers shooting at business owner protecting his property.
https://www.youtube.com/watch?v=Z5tAEzWDsH0
An example of a mentally ill left-winger: listen to how she tries to squirm out of it, like all mentally ill left wingers do. Towards the end of the clip, notice how she starts with the ‘how does this relate’ and the ‘but muh first amendment’ trying to shift the goal posts to distract from her own words and deflect and obfuscate to try to shift burden to Kennedy – notice the similarity in the same types of tactics used by Miner49er… its typical left wing mental illness.):
“Senator Kennedy leaves radical Democrat witness STUNNED after he brought the receipts of her INSANE social media posts!
‘The Supreme Court has embraced the use of the Constitution as a tool of racial patriarchy. Did you say that?!’
‘When the Supreme Court declares that there is a constitutional right to armed self-defense in public, it openly embraces and promotes a culture that privileges white man’s ability to terrorize and kill those that they perceive as threats. Did I read that correctly?!’
‘By simultaneously expanding white man’s right to kill and constricting women’s right not to die, this Supreme Court has turned the Constitution into a homicide pact as well. Did you write that?!’
Her response might just be the most INSANE part of this whole clip: ‘That sounds like me!’ ”
https://x.com/townhallcom/status/1904616539979907145
Real world example here. Sig226 with threaded barrel and Rugged Obsidian 9 suppressed. Running Freedom Munitions HUSH 165gr ammo. The report was quieter than my pellet gun, also quieter than my suppressed .22 running subsonic .22.
I walked around to the other side of my house (1500 sq ft) and let a friend fire a few shots. I could barely hear the shot but heard the steel plate ring. Amazing, nearly “Hollywood” quiet.
We did the same thing with his Smith and Wesson FPC? folding 9mm carbine rifle and I could not hear it fire when other other side of the house. Yes, the round was moving at around 800fps but still enough to do what it needs to do at 50 yards+. Wanted to post for anyone interested in such a setup.
CCityGuy,
I have the Rugged Obsidian 45 and fired a single shot through it from a pistol with 4.5-inch barrel chambered in .40 S&W. It was loud, seemingly a LOT louder than your experience. And it was most definitely a LOT louder than a suppressed .22 rifle shooting subsonic ammunition. I may have some more work to do to figure that out and reduce the sound level (if possible).