Short barrel AR noise levels

[GJM]

In another thread, there was discussion of short barrel AR sound levels in a range setting.

https://pistol-forum.com/showthread.php?57710-Gen-Y-Z-shooter-trends/page10

Another poster and I reported being disturbed by people shooting short AR pistols near us. In the example I gave, my wife and I were down range of the AR shooter, separated by a dirt berm, and the intensity of the shots interfered with our ability to hear our timer's beep and concentrate on the drills we were doing. I was pretty annoyed at the gentleman doing mag dumps of 5.56, out of his shorter than 10.5 barrel AR onto a large piece of steel..... on a pistol bay.

TGS nicely asked if it was age related, and Google says that people with hearing loss are sensitive to loud noises. Between flying and shooting for decades, I am certainly a candidate for hearing loss. The first thing I did was take an online hearing test which reported that my hearing was "normal." The next thing that occurred to me was whether TGS is so young, that his hearing has not fully developed making him more tolerant of loud shots, but I think that is unlikely. :p

I started Googling short barrel 5.56 decibel levels, and it seems that a 10.5 inch barrel is about 162 db. I couldn't find a number for a 7.5 inch barrel but I assume it is higher than for a 10.5.

https://www.ar15.com/forums/armory/-ARCHIVED-THREAD----Ever-want-to-compare-a-Specwar--Omega--Sandman--Surge--YHM--OSS-all-at-once-/20-460124/&page=1

My experience hunting and firing .300 WM class projectiles without ear pro is that you are best off right behind the rifle. Being to the side or down range of the barrel is worse.

Now for some math and science that I need help with. Let's assume a 7.5 AR is 165 decibels, modestly more than from a 10.5. What will the decibels be to the side or down range. Using a MSA Sordin headset rated at 25 db reduction, does that get subtracted from the 165? How do in ear plugs factor in -- is their db rating added, for example 25 + 30 = a 55 decibel reduction? What kind of noise level will be damaging?

[TGS]

To be clear, the difference between a 10" barrel and 16" barrel is only 2db.

The guns are not significantly louder. They have more concussion, but a 16" barrel will fuck up your hearing or interrupt your shot timer just the same as an SBR.

And yes, thank you for taking that question regarding age in the manner it was intended. :)

Re:ear plugs, peterb had posted some articles many years ago about the importance of ear plugs as they absorb certain sound waves which can't be attenuated by muffs. Since then, I make it a standard practice to double up regardless of where I am or what I'm shooting. With plugs and muffs, I feel the concussive "slap" of an SBR, but it's no louder than shooting any other 5.56 rifle.

[GJM]

But aren't increases in decibels like earthquakes:

(From Google) A 1 dB change in a sound equates to about a 26% difference in sound energy (remember that a 3 dB difference is a doubling of energy levels). In terms of subjective loudness, a 1 dB change yields just over a 7% change. A 3 dB change yields a 100% increase in sound energy and just over a 23% increase in loudness.

[Sero Sed Serio]

In no way helpful to the math and science question, but 10 years ago I was comfortable on an indoor range with Sordin ear pro that I believe were rated at 22 dB reduction, even when shooting rifles. Now I double up, foam plugs plus ear pro rated around 30 dab. Even then I find anything super short (in the past month I’ve had the pleasure of being one bay over (indoor) from a 7” 5.56 and some shortened AK pistol-variant with something that mimicked a happy switch and would probably lead to spirited debate with AFT’s general counsel), and both were extremely unpleasant. A year ago I forgot the foamies and just had the muffs, and turned right around and went back outside to rectify that after letting my first .40 round go.

[GJM]

To be clear, the difference between a 10" barrel and 16" barrel is only 2db.

The guns are not significantly louder. They have more concussion, but a 16" barrel will fuck up your hearing or interrupt your shot timer just the same as an SBR.

And yes, thank you for taking that question regarding age in the manner it was intended. :)

Re:ear plugs, peterb had posted some articles many years ago about the importance of ear plugs as they absorb certain sound waves which can't be attenuated by muffs. Since then, I make it a standard practice to double up regardless of where I am or what I'm shooting. With plugs and muffs, I feel the concussive "slap" of an SBR, but it's no louder than shooting any other 5.56 rifle.

I would add that after trying different options, my favorite combination is disposable foam plugs under an amplified headset. Some years back, I was told the military did helicopter noise testing and found the best protection was earplugs under a helmet. The helmet protected against damage from the noise hitting the ear bone.

[Totem Polar]

DB is logarithmic. 3 DB is a doubling of sound pressure. Whether we perceive that increase is subject to a lot of psychoacoustic chicanery, but 3db is nothing to sneeze at.


On the subject of HP, I make my living with my ears, and I always foam plug under E-muffs. If you’re indoors, and you are not doubling up, you’re wrong. And, yes, bone induction is a thing. We only have one set of eyes and ears. Best live like that’s the truth. JMO.

[TGS]

I would add that after trying different options, my favorite combination is disposable foam plugs under an amplified headset.

Ditto. I have some pretty robust yellow foamies that peter B blessed off on, and wear those underneath Peltor ComTacs as they have a significantly better fit than my Sordins. Prior to getting this job and being issued the Peltors, I wore Peltor 7s for the same reason even though the electronics on the Peltor 6s and 7s crapped out in impressively quick fashion, whereas the Sordins still work to this day.

[Jim Watson]

Too bad they don't put the Sordin works in a 30 dB cup.
Or do they under another name?

[flyrodr]

Agree with GJM and others about doubling up with plugs and muffs. And that shooting next to an AR, particularly a short-barreled one, is a pain. Literally. I frequent a nice indoor range owned by the county. It is typical, in that its floors are concrete and walls are block. And the stalls are close, with mesh separations. The RSOs will put up foam sheets against the dividers if you have an AR shooter next to you.

If the RSO forgets and places the loam on your side of the mesh, the blast from an SBR next to you will blow it over, onto you. If it's on the AR shooter's side, it stays put, and reduces the noise slightly. Shooting my scoped rimfire, with front and rear bags, I can watch the crosshairs jump off the bullseye with the AR fires. Not a fan, since most of them are not precision shooters and just like to bang away (although range rules limit shooters to one shot/second).

To be fair, I haven't run into any of the AR shooters to be problematic, so there's that.

On the noise note: Has anyone found a phone app (Android) that is reasonably accurate for measuring dBs?

[GJM]

When I switched optics and put an AEMS on my Rattler, I needed to refine zero on the rifle range. There were a half dozen rifle shooters just finished from a 300 yard match. I gave them the heads up a 5.5 barrel .300 under a shed was going to be ugly. They moved away. With 110 Barnes super sonic, it was nowhere near as bad as being down range of the short 5.56.

[HeavyDuty]

DB is logarithmic. 3 DB is a doubling of sound pressure. Whether we perceive that increase is subject to a lot of psychoacoustic chicanery, but 3db is nothing to sneeze at.


On the subject of HP, I make my living with my ears, and I always foam plug under E-muffs. If you’re indoors, and you are not doubling up, you’re wrong. And, yes, bone induction is a thing. We only have one set of eyes and ears. Best live like that’s the truth. JMO.

I’ve doubled up both indoors and outdoors for years, and I also wear foamies when I play out (very infrequent these days.) I’ve made it to 60 with no tinnitus despite the best efforts of a succession of loud drummers and my own shooting.

[JCN]

DB is logarithmic. 3 DB is a doubling of sound pressure. Whether we perceive that increase is subject to a lot of psychoacoustic chicanery, but 3db is nothing to sneeze at.


On the subject of HP, I make my living with my ears, and I always foam plug under E-muffs. If you’re indoors, and you are not doubling up, you’re wrong. And, yes, bone induction is a thing. We only have one set of eyes and ears. Best live like that’s the truth. JMO.

Ditto. I've gotten in the habit of doing foam electronic plugs under E-muffs. That way, if I need to I can bluetooth a timer beep directly to my electronic plugs under my muffs.

Basically I can choose what and whom I want to hear.

My best understanding of the noxiousness of the SBR 5.56 has to do with the direction of noise rather than the volume of noise itself.

It also probably helps to define the terms and standards of which traditional sound testing occurs.

When I was trying to sort out how loud things were, most of the "industry standard" is 1 m offset of the muzzle.

So you can imagine how that might differ from shooter's ear and that also might differ from the side depending on the muzzle brake or compensator the gun was fitted with (that's why I bought a sound meter so I could test at my ear and in environments that might affect reverberation and reflection).

My impression is that's where a lot of the noxiousness of the SBR comes from, especially laterally on the range.

If you were getting shot at... it would probably sound the same, lol.

My 11.5" MCX got a lot more tolerable after I swapped a brake for a directed birdcage. Less sound waves hitting my chest, too.

[Totem Polar]

I’ve made it to 60 with no tinnitus despite the best efforts of a succession of loud drummers and my own shooting.

Too late for me, a lifetime of music has left me with tinnitus that would drown out your mother in law on a bender.

That's part of why I've sold off my .327 fed wheelies, and most of my .357s. And my AR is a .300 Black.

[awp_101]

Too late for me, a lifetime of music has left me with tinnitus that would drown out your mother in law on a bender.

I’m sorry, can you type louder please?


https://youtu.be/CWWDKZ-kydE?si=5FPSPu88CWAkg6tI

[Malamute]

Has anyone here had any experience with the Black River Tactical Covert Comp or similar muzzle widgets intended to reduce the concussion to the shooter and bystanders?

https://blackrivertactical.com/WP/BRT-Covert-Comp-5-56-p33189471

Reviews seemed to indicate it works to some degree.

[Mark D]

I don't see too many short barrel rifles, but I do see (and hear) some obnoxious muzzle devices. As mentioned upthread, I think brake, compensator, and flash hider design has a huge impact on how obnoxious a rifle is to other shooters.

Also a member of the foamies under e-muffs crew.

[Norville]

Has anyone here had any experience with the Black River Tactical Covert Comp or similar muzzle widgets intended to reduce the concussion to the shooter and bystanders?

https://blackrivertactical.com/WP/BRT-Covert-Comp-5-56-p33189471

Reviews seemed to indicate it works to some degree.

I have one on my 10.5” 5.56. It definitely reduces concussion while shooting, but bystanders report it’s still really loud.

[Paul Blackburn]

I have one on my 10.5” 5.56. It definitely reduces concussion while shooting, but bystanders report it’s still really loud.

It also produces more flash than a A2 birdcage.

[Clusterfrack]

It would be interesting to see the pressure waveform behind and at the side of a rifle with a brake.

My impression is that there are two issues that make it unpleasant. One is the peak loudness of the sound. The other is the blast, even if the ears are well protected. It feels like a slap in the face. I’ve seen people’s hats get blown off. When I’ve had to spot someone with a nasty brake, having a ruck in between seems to help.

[UNK]

I was just at a range where a guy was shooting a short barrel 308 and no silencer. It was horrible. I double up everywhere I shoot because of tinnitus. Loud sharp noises are like someone drove an ice pick into my ear. Higher frequency female voices, yappy little dogs and silverware clatter in a busy restaurant have the same effect.

[Malamute]

It also produces more flash than a A2 birdcage.


That seems like a worthwhile trade to me, less concussive blast for more flash. Others MMV of course. My taste in ARs tends towards 20" barrels in any event, largely due to the less perceived muzzle blast.

[HeavyDuty]

I don't see too many short barrel rifles, but I do see (and hear) some obnoxious muzzle devices. As mentioned upthread, I think brake, compensator, and flash hider design has a huge impact on how obnoxious a rifle is to other shooters.

Also a member of the foamies under e-muffs crew.

I have a linear compensator (I think it’s called, a muzzle device that has forward facing ports) on my 7.5” 5.56 and it does an admirable job blowing concussion forward. Still loud as hell, though.

[HeavyDuty]

I was just at a range where a guy was shooting a short barrel 308 and no silencer. It was horrible. I double up everywhere I shoot because of tinnitus. Loud sharp noises are like someone drove an ice pick into my ear. Higher frequency female voices, yappy little dogs and silverware clatter in a busy restaurant have the same effect.

My ex-wife is an audiologist, and she made me aware of how loss of acuity is common as we age. My hearing is fine, but my ability to pick specific noises out of a soundscape is crap and I’m easily overwhelmed by loud, busy environments like restaurants and concerts. I also has a touch of the autiz which doesn’t help. Music style earplugs are my friend when we go out, I keep them in both cars and have spares.

[TGS]

Anecdotally, this sort of confirms what I was thinking. It seems that the biggest complaints around this topic come from older individuals, particularly those with a history of hearing damage.

Which is a shame, because most of the old people I've interacted with on ranges get all fuddy with, "what's he an assassin!?" comments when I pull out the suppressor for the Mk18 or Mk12. Ditto at work, where the older senior officials tend to be the ones who are most opposed to the idea of LEOs using suppressors.

Come on people. Help us help you. More suppressors is a win-win for us both.

[HeavyDuty]

Come on people. Help us help you. More suppressors is a win-win for us both.

From your lips to BATFE’s ear - my cans are all in jail.

[Totem Polar]

Ditto at work, where the older senior officials tend to be the ones who are most opposed to the idea of LEOs using suppressors.

Come on people. Help us help you. More suppressors is a win-win for us both.

There was pushback a few years back on our local LE universally going the SBR/suppressor route. Fortunately saner minds prevailed.

Straight up: noise safety is OSHA level stuff, with OSHA level codification. The fact that suppressors still have their own uber-tax, as opposed to being tax-exempt, is *objectively* retarded.

To be clear: anyone in the USA should be able to buy a suppressor tax-exempt at the friendly LGS. At least, they should if we are taking safety seriously. JMO.

https://y.yarn.co/c3f2f06b-3130-4d9f-b3ec-b58063683744_text.gif

[DMF13]

Every couple of years someone floats the idea of getting mufflers (technically AND legally correct description ;) ), for our rifles, for use in training, not operationally, to protect our hearing. Every time it gets shot down shot down. :rolleyes:

[TGS]

Every couple of years someone floats the idea of getting mufflers (technically AND legally correct description ;) ), for our rifles, for use in training, not operationally, to protect our hearing. Every time it gets shot down shot down. :rolleyes:

Bosses thinking out loud while inking the "denied" memo:

"Them faggots probably put avocado on their toast and wear baseball caps, too."

[Darth_Uno]

Has anyone here had any experience with the Black River Tactical Covert Comp or similar muzzle widgets intended to reduce the concussion to the shooter and bystanders?

https://blackrivertactical.com/WP/BRT-Covert-Comp-5-56-p33189471

Reviews seemed to indicate it works to some degree.


I have a linear compensator (I think it’s called, a muzzle device that has forward facing ports) on my 7.5” 5.56 and it does an admirable job blowing concussion forward. Still loud as hell, though.

I had a 10.5 5.56 I wanted to like. But no matter what I did it was just way more blast-y (that’s a scientific measurement) than any 11.5 or longer I had.

The Griffin Hammer Comp is stupid loud with this barrel. I tried the Griffin QD Blast Shield, which worked as advertised. But you’re basically putting a mini-suppressor sized device on the barrel that, you know, doesn’t actually suppress anything. Then I tried the Griffin Linear Comp which also worked as advertised (not as well as the Blast Shield) but did nothing to mitigate the giant fireball. But at least it put the concussion into the range of “tolerable” for anyone shooting off to the side.

Anyway if anybody wants a lightly used 10.5” Faxon SOCOM barrel let me know. :cool:

https://www.griffinarmament.com/taper-mount-linear-compensator/

https://www.griffinarmament.com/qd-blast-shield-gen-2/

[Malamute]

I had a 10.5 5.56 I wanted to like. But no matter what I did it was just way more blast-y (that’s a scientific measurement) than any 11.5 or longer I had.

...Anyway if anybody wants a lightly used 10.5” Faxon SOCOM barrel let me know. :cool:




I was somewhat interested in a pistol, to be used as a scoped relatively precision long range pistol, sort of a self loading XP100. The blast issue had me rethinking it, I concluded Remington probably had it about right with the shorter 221 cartridge for use in the XP. My interest in AR pistols waned, Im back to thinking an XP in 221 cal is the answer for me for for long range precision pistol shooting. At the very least i can use the cheap 223/5.56 brass for reforming to 221.

[Mark D]

Just curious, what's the appeal of the super short 5.56 rifles, like 7.5" inches? I was under the impression that 5.56 mm became pretty anemic in barrels shorter than about 10.5".

[Paul Blackburn]

Does the 5" to 9" 300 Black Out not have similar blast/concussion?

[Screwball]

Just curious, what's the appeal of the super short 5.56 rifles, like 7.5" inches? I was under the impression that 5.56 mm became pretty anemic in barrels shorter than about 10.5".

Probably people think they look cool…

My limit is 11.5” in a 5.56mm. To be fair, I think the only sub-10.3” barrel 5.56mm I’ve ever seen really marketed towards L/E was that DPMS Kitty Kat. Stag put out a few and I have seen uppers offered on PSA. But end of the day, it’s more for fun. I have two ARs and a MP5 clone that have binary triggers… completely for fun.

.300 Blackout did change that, as it was optimized for those shorter barrels. I do have a 6” AR, but it is 9mm, takes Glock magazines and is roughly the same OAL as a 16” AR with the Dead Air Odessa.

For my SBRs (minus the 9mms), I usually have something to direct the blast forward. Before suppressors, I had one of the KVPs. It wasn’t bad for the price. I also had a PSA AK-P with their Krink device. Behind the gun, you are good. Off to the side, you feel your guts rattling around.

I switched to the Griffin Taper devices so I could easily swap my Griffin Bushwhacker 46 among ARs… but had to pull it off my truck gun; Taper wouldn’t let the gas piston come out. Put an A2 on and got the A2 adapter from Griffin. It works and gives me flexibility to the couple ARs that I kept the A2 on. I do have their blast forward device, which works well… but when it’s between that and suppressor, I’m picking the suppressor. But the round going supersonic has a lot to do with the added noise. I always double up when shooting rifle rounds. Usually shoot both at the range, so I tend to have both in. But don’t notice a difference between SBRs and 16”+ rifles.

I keep my Bushwhacker on my truck gun majority of the time. Shooting without ears will still cause damage, but less than if it was unsuppressed. I keep a pair of foam plugs tucked on the gun, in case I got the opportunity to toss them in…. but the likelihood is low. In the end, I make sure I use ear protection during training. Hopefully if I had to use the gun(s) in real life, it wouldn’t cause too much damage.

[mmc45414]

Every couple of years someone floats the idea of getting mufflers (technically AND legally correct description ;) )
I have mentioned to people the irony of it being illegal to put a muffler on my gun while being illegal to take the muffler off of my motorcycle, and the people most upset about a loud bike would be the first to wring their hands about "silencers".

Years ago I was shooting next to my friend, he with a 26" Rem700, me with one of my typical 16" ARs, and I was stunned by the realization that ten inches made that much difference (I will say it first: That's What She Said...). I do have a 7.5" upper, but when I bought it I knew it was just a (cheap) silly range toy. TBH, I do not own a can, and I really do not really love the 5.56 cartridge anyway, but is just part of the landscape at this point.

Some of all of this initiated my interest in 300BO, and looking at the powder burn rate chart illustrates this. This is a chart of relative rates, and that may mean there are lots of products between that range, but 300BO is basically working with the slow end of pistol powder:

107501

107502

[O4L]

So I have an 8" 300BK that I haven't fired yet. Am I going to hate shooting it with an A2 style muzzle device?

I have subsonic 150 grain and supersonic 200 grain ammo at this time. I plan on trying 110 grain v-max ammo for hunting.

[GJM]

Purely in the interest of science, I think TGS should arrange to be 25 yards down range of someone with a 7.5 5.56 doing mag dumps on steel in the adjoining bay, and let us know what that sounds like!

[GJM]

So I have an 8" 300BK that I haven't fired yet. Am I going to hate shooting it with an A2 style muzzle device?

I have subsonic 150 grain and supersonic 200 grain ammo at this time. I plan on trying 110 grain v-max ammo for hunting.

I was initially concerned about my Rattler, with a 5.5 inch barrel. With 110 Barnes, it is not anywhere near what I expected. To my ears, an 8 inch .300 BLK is similar or slightly quieter than a 16 inch 5.56.

[O4L]

I was initially concerned about my Rattler, with a 5.5 inch barrel. With 110 Barnes, it is not anywhere near what I expected. To my ears, an 8 inch .300 BLK is similar or slightly quieter than a 16 inch 5.56.Thanks. That is kind of what I was thinking but I haven't really looked into it.

I bought it on a whim because I got a good deal. This is my first 300 BK and my first short barreled AR.

[Kyle Reese]

Just curious, what's the appeal of the super short 5.56 rifles, like 7.5" inches? I was under the impression that 5.56 mm became pretty anemic in barrels shorter than about 10.5".

Some people want to look cool on the range, I suppose. On my personal carbines, I don't go with anything in 5.56 sub 11.5", and those are all shot suppressed.

[HeavyDuty]

Just curious, what's the appeal of the super short 5.56 rifles, like 7.5" inches? I was under the impression that 5.56 mm became pretty anemic in barrels shorter than about 10.5".

Because they’re fun? Some rifles can just be recreational.

My personal crossover point between a serious and non-serious 5.56 is 11.5”, but I do have a new 10.5” upper I’ll be trying out.

A couple of years ago I was offered a deal on a new 5.56 Rattler that was barely more than a lightly used MCX lower end would have cost me. I bought it, of course and it allows me to have a second lower for my set of MCX uppers.

A 5.5” 5.56 is totally impractical and shooting it makes me giggle. I just ordered a .22LR conversion bolt for it so it will have a more practical use, too.

[Spartan1980]

I find SBRs in 5.56 just straight up obnoxious unless suppressed and for this reason all my AR pistols are in 9mm.

GJM I used to shoot a local unsanctioned 3gun match with a guy that ran a NFA'd SBR in .300BO. I would concur with you on the noise level. It's loud but not stupid level loud. That is the only SBR that I would consider using inside the house for defense because just the thought of touching off a 10.5" 5.56 inside the house terrifies me. When I get over my aversion to getting "blessed" I'll pay the tax for a suppressor and build a .300BO pistol for HD. Until then the gage and pistols will have to do.

[HeavyDuty]

I find SBRs in 5.56 just straight up obnoxious unless suppressed and for this reason all my AR pistols are in 9mm.

GJM I used to shoot a local unsanctioned 3gun match with a guy that ran a NFA'd SBR in .300BO. I would concur with you on the noise level. It's loud but not stupid level loud. That is the only SBR that I would consider using inside the house for defense because just the thought of touching off a 10.5" 5.56 inside the house terrifies me. When I get over my aversion to getting "blessed" I'll pay the tax for a suppressor and build a .300BO pistol for HD. Until then the gage and pistols will have to do.

I intend on seeing how this runs suppressed:

https://pistol-forum.com/attachment.php?attachmentid=101528&d=1676660396.jpg

[Paul Blackburn]

Anyone aware of the decibel difference between a 9" 300 BA and a 7.5 556?

[Mark D]

Because they’re fun? Some rifles can just be recreational.

My personal crossover point between a serious and non-serious 5.56 is 11.5”, but I do have a new 10.5” upper I’ll be trying out.

A 5.5” 5.56 is totally impractical and shooting it makes me giggle. I just ordered a .22LR conversion bolt for it so it will have a more practical use, too.


Some people want to look cool on the range, I suppose. On my personal carbines, I don't go with anything in 5.56 sub 11.5", and those are all shot suppressed.


Probably people think they look cool…

My limit is 11.5” in a 5.56mm.

Thanks, I was just curious about the rationale for super short, unsuppressed rifles. They don't appeal to me, but I'm fairly sensitive to noise and blast. I've gotten more sensitive as I've gotten older, which may support the suggestion from @TGS (https://pistol-forum.com/member.php?u=941) that age has something to do with it.

ETA - I also have some hearing damage (infantry, motorcycles, heavy equipment, etc.), so I'm definitely in the demographic described by TGS up thread.

[DDTSGM]

Anyone aware of the decibel difference between a 9" 300 BA and a 7.5 556?

I found 10.5 5.56 and 8" 300BO


10.5" SBR 556
No can
162.4
162.6
160.5
162.6
162.6

16" barrel 556
No can
160.4
160.4
160.4
160.4
160.2

300 blk 8" sbr
No can
154.1
153.8
153.8
153.5

ETA: Loudness is measured on a logarithmic scale. This means that an increase of 10 decibels (dB) represents a 10-fold increase in sound intensity and a doubling of the perceived loudness.

From another source (more trustworthy result than the guy who did the above on the range):

The sound pressure level was measured according to Mil-Std 1474D, which specifies A-weighting. Weighting degrades meter performance to match the frequency response of the human ear, and A-weighting is accurate and appropriate only for sound levels below 55 dB. For sound levels above 130 dB, and in particular in the 160+ dB region of the non-suppressed 5.56mm rifle, the measurements should be performed without any weighting (also called “linear” or Z-weighting, depending on the meter manufacturer’s designation). While there is a rough correlation using A-weighting between uncorking pressure and measured sound level, the sound measurements are not considered overly accurate due to compliance with the Mil-Std.

Sound levels are pressure measurements expressed as a logarithmic ratio of the actual pressure referenced to 20 micro-Pascals, the threshold of human hearing. There was a little less consistency in the sound measurements than in actual uncorking barrel pressure measurements, partially because of adding several more variables. These included the acoustic impedance of the air and wind direction/velocity. In addition, the inaccuracies in this sound intensity range by using the called-for A-weighting introduces some level of inaccuracy that would probably not be seen in unweighted measurements. When pressure is plotted against sound pressure level in decibels and sound pressure level is plotted against barrel length, there is slightly more deviation from the projected average, but the trend and general correlation is statistically meaningful. Actual sound pressure levels varied from 162.5 dB(A) in the 24-inch barrel to 165.1 dB(A) in the 5-inch barrel.


https://sadefensejournal.com/barrel-length-studies-in-5-56mm-nato-weapons/2/#:~:text=Actual%20sound%20pressure%20levels%20vari ed,in%20the%205%2Dinch%20barrel.

“the only potentially effective noise control method to reduce students’ or instructors’ noise exposure from gunfire is through the use of noise suppressors that can be attached to the end of the gun barrel.” – The Centers for Disease Control and Prevention (CDC)

Research that demonstrates the superiority of silencers over traditional ear protection has been published by Matthew P. Branch, MD. He found, “All suppressors offered significantly greater noise reduction than ear-level protection, usually greater than 50% better. Noise reduction of all ear-level protectors is unable to reduce the impulse pressure below 140 dB for certain common firearms, an international standard for prevention of sensorineural hearing loss . . . Modern muzzle-level suppression is vastly superior to ear-level protection and the only available form of suppression capable of making certain sporting arms safe for hearing.”

https://www.ammunitiontogo.com/lodge/silencer-guide-with-decibel-level-testing/

“Noise above 70 dB over a prolonged period of time may start to damage your hearing. Loud noise above 120 dB can cause immediate harm to your ears,” says the Centers for Disease Control and Prevention on its website,

https://hearinghealthfoundation.org/decibel-levels

I know this isn't exactly what you are looking for but I hope it is useful.

I know first hand that being even with the muzzle of a 14.5" 5.56 at a distance of about 3 feet to the right with your left muff cracked causes immediate pain and hearing loss. Went to audiologist a couple days later and got my first hearing aid.

[GJM]

Dan, thanks for this info. Interesting that my "8 inch .300 seems quieter than a 16 inch 5.56" is supported by the data.

[GJM]

As I have more experience (and years) around loud noises, whether they be from aircraft engines or firearms discharging, I am much less tolerant of noise levels that will damage my hearing. I am not sure how much of that is physical tolerance and how much is a desire to protect my hearing.

[HeavyDuty]

I know first hand that being even with the muzzle of a 14.5" 5.56 at a distance of about 3 feet to the right with your left muff cracked causes immediate pain and hearing loss. Went to audiologist a couple days later and got my first hearing aid.

That is terrifying.

I sometimes get looks from the bucks for inserting foamies and muffing up well clear of the range. Youth is wasted on the young.

[TGS]

That is terrifying.

I sometimes get looks from the bucks for inserting foamies and muffing up well clear of the range. Youth is wasted on the young.

If I'm at an outdoor range, I usually insert the foamies while still in my vehicle and throw on the muffs while getting my stuff from the hatch before walking up to the benches.

GJM To be clear, my intention was never to doubt that gunshots without hearing protection is painful and dangerous. I don't think I'm cavalier about hearing protection, either, given I've been doubling up for years and actually put thought and basic research into the specific earplugs I chose to buy in bulk, and have talked to 3 different industrial safety officers gathering their thoughts on hearing protection issues.

When doubled up, however, they all sound like muffled pops. I can't tell a difference in loudness from one 5.56 to another while doubled up on ear pro, and I certainly for sure as shit cannot tell a difference in loudness between a 1200fps 9mm load and 1400fps 9mm load. I have never been down range of a 7.5" 5.56, but I've been downrange of 5.56 automatics in 10", 14", and 20" barrels (without a berm separating us) for literally tens of thousands of rounds and can't tell a difference in loudness through my ear pro from one to the other. The concussion of an SBR is certainly something of note, but loudness...no difference, no ear pain or discomfort ever noted.

[HeavyDuty]

If I'm at an outdoor range, I usually insert the foamies while still in my vehicle and throw on the muffs while getting my stuff from the hatch before walking up to the benches.

GJM To be clear, my intention was never to doubt that gunshots without hearing protection is painful and dangerous. I don't think I'm cavalier about hearing protection, either, given I've been doubling up for years and actually put thought and basic research into the specific earplugs I chose to buy in bulk, and have talked to 3 different industrial safety officers gathering their thoughts on hearing protection issues.

When doubled up, however, they all sound like muffled pops. I can't tell a difference in loudness from one 5.56 to another while doubled up on ear pro, and I certainly for sure as shit cannot tell a difference in loudness between a 1200fps 9mm load and 1400fps 9mm load. I have never been down range of a 7.5" 5.56, but I've been downrange of 5.56 automatics in 10", 14", and 20" barrels (without a berm separating us) for literally tens of thousands of rounds and can't tell a difference in loudness through my ear pro from one to the other. The concussion of an SBR is certainly something of note, but loudness...no difference, no ear pain or discomfort ever noted.
If you ever care to share specific earplug information…

I agree - I don’t hear volume differences, but I definitely feel concussion differences.

[GJM]

I should probably get some more Peltors. I have had multiple pairs over the years, but they are all now broken. The Sordin muffs keep functioning. Interestingly, sometimes my Open gun loads cause the Sordins to turn off. What are the preferred Peltors these days?

[DDTSGM]

What are the preferred Peltors these days?

I'm not on the cutting edge of anything, but I like my ProTac Shooters. 26db NRR, don't know if the gel pads increase that any.

[DDTSGM]

That is terrifying.

I sometimes get looks from the bucks for inserting foamies and muffing up well clear of the range. Youth is wasted on the young.

I don't remember why I wasn't doubled up with foamies that day, but I wasn't. We had a huge gumball thingie in the range house that dispended them (for free) and I always double protected - well almost.

[DDTSGM]

The concussion of an SBR is certainly something of note, but loudness...no difference, no ear pain or discomfort ever noted.

A lot of folks don't consider that sound is pressure.

After I toasted my left ear I had routine audiology visits every six months. I was religious about double protection, yet from the baseline established my high frequency began dropping rapidly in both ears.

I couldn't figure out why, until one day it dawned on me that when I was coaching or shooting @ 25 yards I could feel the concussion from the shots bouncing off our barricades, off the canopy covering the 25 yard line, and off the range tower, if I was in the middle of the line.

I figured I was getting a double or triple dose of the reverberating waves. I believe that is was a contributing factor to my rapid high frequency loss. Problem was none of my fellow instructors reported the same experience.

Genetics? My Grandpa was deaf as a post by the time he was 70, my dad died young enough that he hadn't evidenced any hearing loss, so IDK.

[HeavyDuty]

A lot of folks don't consider that sound is pressure.

After I toasted my left ear I had routine audiology visits every six months. I was religious about double protection, yet from the baseline established my high frequency began dropping rapidly in both ears.

I couldn't figure out why, until one day it dawned on me that when I was coaching or shooting @ 25 yards I could feel the concussion from the shots bouncing off our barricades, off the canopy covering the 25 yard line, and off the range tower, if I was in the middle of the line.

I figured I was getting a double or triple dose of the reverberating waves. I believe that is was a contributing factor to my rapid high frequency loss. Problem was none of my fellow instructors reported the same experience.

Genetics? My Grandpa was deaf as a post by the time he was 70, my dad died young enough that he hadn't evidenced any hearing loss, so IDK.

Man, I wish I was still talking to my ex (the audiologist.) I wonder if there’s sinus involvement?

[DMF13]

I should probably get some more Peltors. I have had multiple pairs over the years, but they are all now broken. The Sordin muffs keep functioning. Interestingly, sometimes my Open gun loads cause the Sordins to turn off. What are the preferred Peltors these days?I have been using the Peltor Tactical 500 (26dB NRR), witn added gel ear seals, for several years. The headband sucks, but you can add a pad. Other than the headband they are great.

However, if I had to replace them, I'd just get these: https://www.amazon.com/3M-Pro-Protect-Electronic-Protector-Technology/dp/B08WK79727/ref=mp_s_a_1_5_sspa?crid=164QFE0CS6ULQ&keywords=peltor+bluetooth+hearing+protection&qid=1690173041&sprefix=peltor+bluetoot%2Caps%2C540&sr=8-5-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9waG9uZV9zZWFyY2hfbXRm&psc=1

I will when shooting by myself, I skip the electronic ear pro, and use these: https://www.amazon.com/3M-90565-4DC-PS-Pro-Grade-Earmuff/dp/B01MXYJ2QP/ref=mp_s_a_1_3?crid=1XX0Y2376AWIA&keywords=hearing+protection+ear+muffs&qid=1690173178&sprefix=hearing+protection%2Caps%2C1227&sr=8-3

[mmc45414]

If you ever care to share specific earplug information…
This is another aspect of this. I bought some lower rated foam plugs thinking they would be more comfortable, and they are, but they are not enough for shooting. Still handy for the mower and the motorcycle (probably optimal on the motorcycle, when you want a little more sound transmission), and more comfortable if I am going to double up with muffs. So now I end up with somewhat of an informal assortment of foam plugs.

If I am just shooting pistols I am OK with either or, as long as the foam plugs are the higher rated and are inserted well. Also, if I am out for several hours at a 2/3-gun match I am OK with the plugs, and they are adequate for me when I am shooting my 18" 5.56 gun (ETA: Outdoors, I almost never shoot indoors, mainly because I do not like the noise). But I watch out for the people with the brakes and I will put my fingers on top of the foam plugs until they finish with their rifle string.

One nice advantage of doubling up with electronic muffs I enjoy is being able to amplify them so I can still hear speaking through the plugs.

[Robinson]

One nice advantage of doubling up with electronic muffs I enjoy is being able to amplify them so I can still hear speaking through the plugs.

This is something I deal with when attending a shooting class. I already have hearing damage and tinnitus (detailed elsewhere in a forum post) so I often have trouble understanding what the instructor is saying. At the last class I attended I wore my hearing aids beneath my electronic muffs. This solved the problem with understanding the instructor, but probably left me more vulnerable to further damage.

Any other time I shoot I always double up with plugs and muffs. My rifle is suppressed. I keep electronic muffs next to my nightstand gun just in case I have time to put them on. Something that is always in the back of my mind is if I ever have to use my carry gun in self defense there is a good chance it will leave me deaf or close to it.

Regarding the noise reduction resulting from using both plugs and muffs, I know that using 30db plugs plus 30db muffs does not provide 60db of noise reduction. I don't know how to calculate the actual reduction but I know that's not how it works.

The damage noise does to ears is also very dependent on the person. There are people who have been exposed to gunshots a bunch of times who have good hearing. In my case, a combination of noise exposure from farming, playing rock music, hunting without muffs, riding a motorcycle, etc... plus one incident of being exposed to multiple gunshots caused permanent severe damage in one ear and moderate damage in the other. We aren't all affected the same by noise.

[Malamute]

This is something I deal with when attending a shooting class. I already have hearing damage and tinnitus (detailed elsewhere in a forum post) so I often have trouble understanding what the instructor is saying. At the last class I attended I wore my hearing aids beneath my electronic muffs. This solved the problem with understanding the instructor, but probably left me more vulnerable to further damage.

Any other time I shoot I always double up with plugs and muffs. My rifle is suppressed. I keep electronic muffs next to my nightstand gun just in case I have time to put them on. Something that is always in the back of my mind is if I ever have to use my carry gun in self defense there is a good chance it will leave me deaf or close to it.

Regarding the noise reduction resulting from using both plugs and muffs, I know that using 30db plugs plus 30db muffs does not provide 60db of noise reduction. I don't know how to calculate the actual reduction but I know that's not how it works.

The damage noise does to ears is also very dependent on the person. There are people who have been exposed to gunshots a bunch of times who have good hearing. In my case, a combination of noise exposure from farming, playing rock music, hunting without muffs, riding a motorcycle, etc... plus one incident of being exposed to multiple gunshots caused permanent severe damage in one ear and moderate damage in the other. We aren't all affected the same by noise.

Another factor some dont seem to understand is the "auditory exclusion" or not being as aware of gunshots in stressful or hunting situations, does not provide protection, it just means you werent focused on and as aware of the noise.

[mmc45414]

rock music
If I did a list of all of the dumb shit I ever did, sitting on the couch next to those ginormous Cerwin-Vega speakers my friend had (that never really did sound all that good anyway...) would make the list.

[DDTSGM]

Man, I wish I was still talking to my ex (the audiologist.) I wonder if there’s sinus involvement?

IDK

Shortly after I got got the second hearing aid (for my right ear) I suffered a pretty severe concussion. I suffered from vertigo for a while and when I saw an ENT he told me that I had fractured both temporals - he was using layman terms as I later discovered, didn't tell me which part(s) - and that the vertigo would likely go away, it did. However, I lost most of my 'seat of the pants' directional feel as it pertains to driving and riding.

Don't know if that has contributed to subsequent hearing loss.

I've had several MRI's and CT's in conjunction with all this stuff and no one has mentioned sinus.

[TGS]

If you ever care to share specific earplug information…

I'm not home right now, but I'm pretty sure I have these 3M EARSoft plugs:

https://www.3m.com/3M/en_US/p/d/b00017636/

It's only slightly tapered and has a smooth exterior texture, as opposed to the common plugs I've seen on ranges. These are ones with a heavier taper to maximize comfort, which reduces the attenuation: https://www.3m.com/3M/en_US/p/d/v000181515/

And then there's these which are cheap and very common, but have a rough foam exterior that I find irritate my ear canals: https://www.3m.com/3M/en_US/p/d/b00017635/

It looks like 3M has a few other options these days. I bought a case of earplugs around 10+ years ago and am still working them down. To be honest, I also don't think I've ever seen a single person put foam earplugs in correctly. Even if they roll them up first, most people seem to just smash them in their ear instead of using heir opposite hand to reach over top their head and lift their ear up, allowing full access to the ear canal. Without doing that, the plugs will not sit at a proper depth.

[GJM]

Do the Peltor Comptac VI headsets really only have a 23 decibel NRR?

[DDTSGM]

Pretty sure 32 -33db NRR ) are as high as it gets with foam plugs. Those are the ones we had in the gumball dispenser. We also demonstrated proper insertion.

https://www.cdc.gov/niosh/mining/content/earplug.html


https://www.youtube.com/watch?v=kMMHudYoQ40

[TGS]

Do the Peltor Comptac VI headsets really only have a 23 decibel NRR?

That sounds about right, since they're low profile muffs designed to fit underneath a helmet. My Sordins are only 18db nrr, if I remember correctly. Howard Leight Impact Sports are only 21db nrr, as well, compared to their Impact Pros with 30db nrr.

I guess the takeaway is don't buy low profile muffs if you need more protection and don't need the low profile.

[GJM]

That sounds about right, since they're low profile muffs designed to fit underneath a helmet. My Sordins are only 18db nrr, if I remember correctly. Howard Leight Impact Sports are only 21db nrr, as well, compared to their Impact Pros with 30db nrr.

I guess the takeaway is don't buy low profile muffs if you need more protection and don't need the low profile.

Thanks, just ordered the Impact Pros. Those and foam plugs should be the trick.

[TGS]

Thanks, just ordered the Impact Pros. Those and foam plugs should be the trick.

Were you able to find them with gel cups?

[GJM]

Were you able to find them with gel cups?

Missed that, but for $18.97 bought them separately from Amazon as well.

[Default.mp3]

Thanks, just ordered the Impact Pros. Those and foam plugs should be the trick.I would not bank too hard on it being any more than a minor difference if you're already doubling up. For example, the Ops-Core NFMI plugs provide an NRR of 30 dB by themselves, and when paired with the AMP that has an NRR of 22 dB, has an overall NRR of 34 dB. Change that to muffs that have an NRR of 27 dB with plugs with an NRR of 30 dB, and you only get to an NRR of 35 dB. The general rule of thumb used by occupational safety professionals is only to add a maximum of 5 dB of protection to the piece of hearing protection that has the higher rating, regardless of the rating of the second piece of ear pro.

[mmc45414]

Missed that, but for $18.97 bought them separately from Amazon as well.

I was just coming here to post that I added these (https://www.amazon.com/gp/product/B0822RGZH8/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1)and really enjoy extra comfort and protection.

[JSGlock34]

I built this 'retro' gun almost a year ago - turned out to be a really fun project. It's an 11.5" barrel with a pinned and welded faux XM177 muzzle device.

107580

The rifle is a great deal of fun to shoot. Unfortunately, that faux muzzle device - although based on the XM177 moderator - is more like an amplifier. The gun has significantly more concussion than any of the 10.3" or 10.5" guns I own or have shot. It is genuinely unpleasant for anyone lateral to the shooter. I'm not quite sure why exactly that rifle is so much louder, but the concussion is noteworthy and often draws comment at the range. If I were to build it again, I'd just get a 16" barrel (maybe with a slip over fake moderator to complete the cosmetic look...maybe...).

[DMF13]

I didn't realize anyone started making gel seals for the H-L earpro. They weren't available many years ago. Now that gel ear seals are available, I wish I still had my Impact Pros. My only gripe with them was the foam seals quickly wore out, became uncomfortable, and didn't seal well.

[BWT]

I double muff.

Always. I hate to say it were ignorant on lots of things and I think hearing science is one of them. And… it’s financially incentivized by large organizations to not publicize that they have employees in non-hearing safe work environments and makes them financially liable.

Such as the government for military (via VA disability payments) and companies via class action lawsuits.

I’m not a big conspiracy theorist about it, but I think just like so many other things. In 20-40 years we’ll be horrified to learn what was considered acceptable today.

I just operate off that assumption and over-kill ear pro with plugs and Howard Leigh.

I should get a rifle suppressor for my SBR’s in case I ever have to shoot it in home defense… honestly a PCC makes a lot of sense for this reason. Subsonics and plethora of JHP.

[Chuck Whitlock]

When doubling up, do the plugs need to be foam? I have a set of Surefire EP3s or EP4s that are easier to deal with than foam plugs.

I'm leery of the gel pads, due to a silicone allergy.......I've got a scar on the bridge of my nose from a reaction to my first CPAP mask.

[DDTSGM]

When doubling up, do the plugs need to be foam? I have a set of Surefire EP3s or EP4s that are easier to deal with than foam plugs.

I'm leery of the gel pads, due to a silicone allergy.......I've got a scar on the bridge of my nose from a reaction to my first CPAP mask.

According to Surefire the EP3's are NRR 24db. IDK what muffs you are wearing over them.

To figure protection when doubling up you take the highest NRR and then add 5 for the total NRR.

So, using the Surefire EP3's @ 24db NRR and the Peltor ProTac Shooter muff that I wear, 26db NRR, the Peltor at 26db is higher, so you would add 5db to come up with a NRR of 31db.

Here is a snippet about the quick and dirty rule of thumb +5db to the highest NRRand a link to the 'science' -

For dual protection (when ear muffs and plugs are used simultaneously) use the following:

Check the NRR between muff and plug and use the highest one.

If using A-weighted sound level data, correct the NRR above subracting 7dB

For adding the other remaining and less efficient protector NRR, simply use arbitrary value of 5 dB

https://www.linkedin.com/pulse/do-math-dont-get-too-excited-calculate-double-hearing-gaspar


You are almost always going to be better off using 'good' foam ear plugs than any type of passive (versus electronic) 'pass through' plugs.

Here is an example of what I consider a 'good' in the ear electronic plug (kind of):

https://proears.com/product/stealth-28-ht/

The only downsides are you run a cable under your ear pad and you have something on your neck.

I currently wear Elgin Rumbles (27db NRR) under my helmet when I ride, but they don't have amplification, they are more plugs with blue tooth speakers in them.

I'm getting the Stealths from ProEars, will let you know how they work. I'm glad to get something that doesn't have bluetooth.