db At the Shooters Ear Question

[krowpots]

Hi Folks, back with some questions about db at the ear for suppressed AR15s.

I buy suppressors to reduce sound to me in all circumstances, which basically boils down to hunting, outdoor ranges, and home defense. I very likely will never be taking doors or shooting at people who are shooting back. Therefor I am looking for a suppressor that reduces the most sound at my ear, so right off the bat if anyone has suggestions for this on a 16in 5.56 AR, please post up!

I read recently that almost regardless of the db reduction 4ft from the muzzle, using a standard AR the shooters right ear will experience 141-144db. This seems to be confirmed by the recent silencershop tests where they started to take at the ear readings. Suppressors at are getting 134db using the normal metering, are getting 141db at shooters ear: https://www.youtube.com/watch?v=0L6lZ3Pi3Fc (they have many more examples).

The consensus seems to be that this is caused by the action/bcg venting of the AR15 and the increased pressure due to the suppressor. So first question: is this information correct?

Tuukka from Ase Utra suppressors stated on ARFCOM that using an adjustable gas system nets a 1-4db reduction at the ear. Does anyone have any experience with that? Other manufacturers mention that decreasing back pressure reduces sound to the shooter, which seems to fit this hypothesis. Anyone know if this is correct? If so which suppressors generate the least back pressure? Are there any that do this, and don't cost $2200 like the OSS or $1500 like the Surefire?

To further muddy the waters, it seems that at the ear the superlative arms piston kit significantly reduces db at the ear when in bleed-off mode vs. restricted mode. Unfortunately he doesn't compare it to DI: https://www.youtube.com/watch?v=Cy5XLr3igaU So maybe a piston (shudder) and/or venting excess pressure further from the shooter reduces db at the ear?

Thanks for any info you guys have on the subject!

[a_canadian]

Talking from a total lack of experience with the firearm you're using here, but... on the face of it the likelihood seems that at best your platform might be borderline hearing safe, even optimally adjusted with the ideal suppressor for that setup. Perhaps worth looking into other platforms for your uses, something where gas piston mechanisms aren't part of the equation? If that's ridiculous, my apologies. Just saying that if you want to preserve your hearing in all your shooting situations without resorting to ear plugs, going to something inherently quiet at the shooter's ear seems advisable.

[krowpots]

Silencer Shop actually tested a TAVOR and it was worst at the shooters ear. I really cannot think of another platform that both excels at both home defense and hunting and would produce less noise at the ear? I am unsure, especially because of the Superlative Arms test differences. If anyone has any data on other piston guns and platforms like the FN FAL (which as a system similar to the Superlative Arms) or AK, post up!

I am aware that it is close to hearing safe, and the suppressor is already saving a lot of my hearing. I also do use earplugs at the range or basically any time I've planned to shoot that isn't a hunt (during which maybe 2-3 shots get taken generally). I am just looking to see if there is a way to improve it further.

[Deserteaglexxx]

I just got my db meter for testing this exact thing, I will get some numbers with a couple different rifles and cans that I have now and do more when I receive others I have ordered. I think the same way I want the one that is quietest at my ear not the muzzle but I am new to suppressors and want to test many different setups.

[krowpots]

Wow that sounds perfect! I am very much looking forward to your data, as I am sure many others are on this board.

[Deserteaglexxx]

Ok I got out today to test 3 different cans: silencerco hybrid, silencerco omega and the Oss elite. All were shot using m193 ball through a bcm 11.5" upper with Jp silent capture spring. I'll just give averages at this point, when I get more organized and can detail everything out I will, I took the measurements in 3 spots and all were 5 shot groups. 1 meter left of bore, shooters right and left ears, with the Larson Davis lxt1-qpr C weighted.

Base line was: 2 shots 169.7 and 170

Oss elite:
1 meter left: 140.64 avg.
Shooters right ear: 137.36 avg.
Shooters left ear: 138.18 avg.

Sico omega with 5.56 end cap:
1 meter left: 142.18 avg.
Shooters right ear: 139.58 avg.
Shooters left ear: 136.8 avg.

Sico hybrid 5.56 end cap:
1 meter left: 141.78 avg.
Shooters right ear: 138.34 avg.
Shooters left ear: 136.18 avg.

[mars]

i know you've got a 556, but switch out your barrel to a 300 blkout. you can use supers (with hearing protection) for hunting and subs for home defense. 300 blkout in subsonic rounds measured ~125 db, which is hearing safe.

[tf2addict]

I wouldn't worry about 142 dB for home defense. For everything else I would still be wearing ear pro. anyway.

[whiterussian1974]

During a Home Invasion, your adrenaline will be so high that your Inner Ear bones will pull apart and not transmit much sound. But the cilia will get a pounding from the echos off the walls and ceiling. The trade-off is, you save your life, but get Tinnitus.

I guess that you could keep ear plugs or muffs near you carbine and slip them on if you have time. Or just suffer the consequences of staying alive.

I tend to put an ear plug in my right ear no matter what during shooting. That's closer to the ejection port, and that way I save at least 1 ear for my Dotage. (I'm pretty close as it is. )
---
PS. I'd also switch to 300BLK for Home Defense. The larger frontal area will help stop the Threat, instead of just perforating organs that will eventually bleed out and kill him AFTER he's harmed your Family.

If possible, use fragmenting rds. Those that split into 4 segments are really great for Terminal Upset. But even the ones that snap at the shank into Tip and Base at least create 2 separate wound channels to increase Nerve Bundle Shock.

[Flakbait]

I concur with using an earplug in the right ear using 5.56. I have shot a 16 in barrel AR15 in 5.56 using 55 grain and 62 grain ball ammo with a Silencerco Specwar 5.56 can. This combination has been tested by various sources to be under the "magical" 140 dB limit near the muzzle but borderline at the right ear for a right handed shooter due to ejection port noise.

Without an ear plug in the right ear it is very unconfortable to me for more than a few rounds. I doubt any suppressor combination or piston will dramatically lower the noise significant enough to make it comfortable.

Either switch to 300 blackout or wear at least one ear plug in the right for extended shooting. For a range toy, consider a variety of semiauto submachine gun that fire 147 grain 9 mm ammo. Whatever the host, they are usually quieter and more economical that 5.56 or 300 blackout if you are just punching holes in paper or ringing steel at 100 yards or less.

[whiterussian1974]

I concur with using an earplug in the right ear using 5.56. Either switch to 300 blackout or wear at least one ear plug in the right for extended shooting.

For a range toy, consider a variety of semiauto submachine gun that fire 147 grain 9 mm ammo. Whatever the host, they are usually quieter and more economical that 5.56 or 300 blackout if you are just punching holes in paper or ringing steel at 100 yards or less.

Thank you for validating my post.

Sadly, I must slightly differ in my recommendation for subguns. For Home Defense, I'd choose .45ACP if you're wanting a lower cost ammo. It's Frontal Area and Turbulent Upset are better than 9mm for CQB. Lots of great fragmenting ammo for Home Use. 3-6 Petals and the flat Base.

But 9mm is cheaper and GREAT for range fun!!! So I'm also agreeing w you there.

I personally have my Glock 22 .40 on the nightstand, and a 9x39 AK near the Bedroom door in a wall safe that I open when home.
-If they're entering the Bedroom, .40 95gr Aguila "IQ" fragmenting rds @ 1350fps.
-If they're still in the Main Area or outside, 250gr .356 @ 965fps for better range and accuracy from cover.

[whiterussian1974]

My Nightstand Pistol/can:

SP5 and SP6 bullets for review:

My Bullpup AK:

And a Low Cost option that is on the Net:

[krowpots]

Thanks for the great data Deserteaglexxx!! Looks like a .30cal can is the way to go.

Please keep us updated if you test any more!

[tf2addict]

PS. I'd also switch to 300BLK for Home Defense. The larger frontal area will help stop the Threat, instead of just perforating organs that will eventually bleed out and kill him AFTER he's harmed your Family.

If possible, use fragmenting rds. Those that split into 4 segments are really great for Terminal Upset. But even the ones that snap at the shank into Tip and Base at least create 2 separate wound channels to increase Nerve Bundle Shock.

Most 223/556 rounds will fragment and in a lot more than 4 pieces and do tremendous damage. Supersonic 300BLK will be more likely to overpenetrate. Subsonic and you're talking effectiveness on par with a .45 handgun, I'd rather have a 5.56 for sure.

[tf2addict]

For Home Defense, I'd choose .45ACP if you're wanting a lower cost ammo. It's Frontal Area and Turbulent Upset are better than 9mm for CQB. Lots of great fragmenting ammo for Home Use. 3-6 Petals and the flat Base.

Your ballistic opinions are wildly off base. I don't even know what Turbulent Upset means, do you mean tumbling or do you mean temporary cavitation? I have never seen the term Turbulent Upset in any ballistics literature, have you? If you have I'd love to see a reference.

Handgun JHPs do not tumble. Nor do they create significant enough cavitation, in any caliber (with the possible exception of Magnums and very high power handguns), to be a factor in stopping power. And almost no one recommends fragmenting rounds for handguns, they severely underpenetrate.

[fishman]

PS. I'd also switch to 300BLK for Home Defense. The larger frontal area will help stop the Threat, instead of just perforating organs that will eventually bleed out and kill him AFTER he's harmed your Family.

If possible, use fragmenting rds. Those that split into 4 segments are really great for Terminal Upset. But even the ones that snap at the shank into Tip and Base at least create 2 separate wound channels to increase Nerve Bundle Shock.

Most 223/556 rounds will fragment and in a lot more than 4 pieces and do tremendous damage. Supersonic 300BLK will be more likely to overpenetrate. Subsonic and you're talking effectiveness on par with a .45 handgun, I'd rather have a 5.56 for sure.

if you handload, supersonic 30 cal varmint bullets in 300 blackout would not overpenetrate and would be a better choice than a fragmenting 223/556 imo. not sure if there are any think jacket hollow point factory loads out there though.

also, 300 blk is superior in an SBR, which is preferred for HD scenarios.

[krowpots]

Folks, I believe we have gotten a bit off topic. This thread is about metering numbers for suppressor at the shooter's ear not the 100 billionth caliber wars thread. If you want to have that conversation, there are plenty of other places that would be more than happy to debate it all day long.

Moving on, this seems to be a pretty decent resource for numbers in addition to the ones already posted ITT (thanks again): https://modernrifleman.net/suppressors/ I am hoping more folks can fill in this list, there are a lot of suppressors and a lot more ar15 configurations we just don't have good data for.

[fishman]

Folks, I believe we have gotten a bit off topic. This thread is about metering numbers for suppressor at the shooter's ear not the 100 billionth caliber wars thread. If you want to have that conversation, there are plenty of other places that would be more than happy to debate it all day long.

Moving on, this seems to be a pretty decent resource for numbers in addition to the ones already posted ITT (thanks again): https://modernrifleman.net/suppressors/ I am hoping more folks can fill in this list, there are a lot of suppressors and a lot more ar15 configurations we just don't have good data for.

i suppose we did get off topic justifying 300 blackout over 223/556 in order to reduce db at the shooter's ear.

Back on Topic:
yes an adjustable gas block can help a little in either case, as can handloading.

just speculating, but i bet a carbine piston gas system under a tubular freefloat rifle length handguard would be quieter (to the shooter) than DI. vented gasses would get trapped under the handguard and travel away from the shooter.

the bottom line is:
if you have to, or want to, shoot 556, slap a silencer on there and deal with it not being hearing safe without hearing protection.
if you have to, or want to, shoot hearing safe at your ear, shoot a pistol caliber or 300 blackout AR (or a dedicated subgun.)


have your cake or eat it. Just my $0.02

[krowpots]

fishman I'm not sure if you've been paying attention to the thread. A 5.56 can certainly be made "hearing safe" (<140db) with the right suppressor (SiCo Omega/hybrid, OSS, Sig SRD 762, probably more but we don't have confirmation).

Piston systems make ARs louder because of the violent slapping action and early unlock.

You should always wear hearing protection, even when shooting subs because 120db is still damaging over time.

[Bendersquint]

Piston systems make ARs louder because of the violent slapping action and early unlock.

They are louder because of the venting of the gases, not violent slapping action or early unlock.

[whiterussian1974]

To address Dr 70posts' concerns:

For Home Defense, I'd choose .45ACP if you're wanting a lower cost ammo. It's Frontal Area and Turbulent Upset are better than 9mm for CQB. Lots of great fragmenting ammo for Home Use. 3-6 Petals and the flat Base.

Your ballistic opinions are wildly off base. I don't even know what Turbulent Upset means, do you mean tumbling or do you mean temporary cavitation?

Handgun JHPs do not ... create significant enough cavitation, in any caliber (with the possible exception of Magnums and very high power handguns), to be a factor in stopping power. And almost no one recommends fragmenting rounds for handguns, they severely underpenetrate.

By "Turbulent Upset" I meant a phenomena related to https://en.wikipedia.org/wiki/Hydrostatic_shock and Energy Transfer to semi-elastic internal organs such as Liver/Spleen/Kidneys and Nerve Bundles.
---
And was relating my understanding of Cpl Ed Sanow's Handgun Stopping Power and Street Stoppers.
http://www.stoppingpower.net/books/book_street.asp
- The eagerly anticipated street results of the hottest new caliber to hit the shooting world in years - the .40 Smith & Wesson.
- The first formal presentation in print of the controversial Strasbourg Tests, which recorded the effectiveness of handgun loads fired into live goats.
- Updated street results of the latest exotic ammunition, including Remington Golden Saber and CCI-Speer Gold Dot, plus the venerable offerings from MagSafe, Glaser, Cor-Bon, and others.
- A powerful new formula to predict handgun stopping power - the Fuller Index.

Plus:
- Wound Ballistic Workshop: "9mm vs. .45 Auto", FBI Academy, Quantico, VA, September 1987. Conclusion of the Workshop.
- Patrick, Special Agent Urey W. (14 July 1989). "Handgun Wounding Factors and Effectiveness" (PDF). Quantico: Firearms Training Unit, FBI Academy.
- Courtney A, Courtney M (2007). "Links between traumatic brain injury and ballistic pressure waves originating in the thoracic cavity and extremities" (PDF). Brain Injury. 21 (7): 657–662.
- Suneson A, Hansson HA, Seeman T (1990). "Pressure Wave Injuries to the Nervous System Caused by High Energy Missile extremity Impact: Part II. Distant Effects on the Central Nervous System. A Light and Electron Microscopic Study on Pigs.". The Journal of Trauma. 30 (3): 295–306.

This chart and real life shooting events beg to differ w you about the advisability of fragmenting cartridges.
http://www.chuckhawks.com/handgun_power_chart.htm

[fishman]

fishman I'm not sure if you've been paying attention to the thread. A 5.56 can certainly be made "hearing safe"[...]

You should always wear hearing protection, even when shooting subs because 120db is still damaging over time.

i guess that comes down to the definition of hearing safe. If you're going to be using hearing protection then none of this really matters that much.
I'd be 100% comfortable submitting my ears to 140dB while hunting, or in a defensive scenario. Hell, I already put up with shooting unsupressed 12ga, .223, and .270 in limited amounts. like you said, 140 is not safe at the range during extended periods of time. all i was trying to say was, dont shoot a supressed .223 a lot and expect your ears to be safe without protection. I'd be a lot more comfortable shooting a suppressed subgun or 300 blackout that metered somewhere near 120db without hearing protection for somewhat extended periods. the difference between 140dB and 120dB is a factor of 4. even OSHA permits continuous 115dB noise levels for up to 15 minutes at a time (practicing with a firearm is not even close to continuous noise). Im not quite sure where we're disagreeing.

[kiwi collector]

Ok I got out today to test 3 different cans: silencerco hybrid, silencerco omega and the Oss elite. All were shot using m193 ball through a bcm 11.5" upper with Jp silent capture spring. I'll just give averages at this point, when I get more organized and can detail everything out I will, I took the measurements in 3 spots and all were 5 shot groups. 1 meter left of bore, shooters right and left ears, with the Larson Davis lxt1-qpr C weighted.

Base line was: 2 shots 169.7 and 170

Oss elite:
1 meter left: 140.64 avg.
Shooters right ear: 137.36 avg.
Shooters left ear: 138.18 avg.

Sico omega with 5.56 end cap:
1 meter left: 142.18 avg.
Shooters right ear: 139.58 avg.
Shooters left ear: 136.8 avg.

Sico hybrid 5.56 end cap:
1 meter left: 141.78 avg.
Shooters right ear: 138.34 avg.
Shooters left ear: 136.18 avg.

Were you using C weighted instead of the normal A weight because you wanted to get a true sound test level that people actually hear

[owensww]

Ok I got out today to test 3 different cans: silencerco hybrid, silencerco omega and the Oss elite. All were shot using m193 ball through a bcm 11.5" upper with Jp silent capture spring. I'll just give averages at this point, when I get more organized and can detail everything out I will, I took the measurements in 3 spots and all were 5 shot groups. 1 meter left of bore, shooters right and left ears, with the Larson Davis lxt1-qpr C weighted.

Base line was: 2 shots 169.7 and 170

Oss elite:
1 meter left: 140.64 avg.
Shooters right ear: 137.36 avg.
Shooters left ear: 138.18 avg.

Sico omega with 5.56 end cap:
1 meter left: 142.18 avg.
Shooters right ear: 139.58 avg.
Shooters left ear: 136.8 avg.

Sico hybrid 5.56 end cap:
1 meter left: 141.78 avg.
Shooters right ear: 138.34 avg.
Shooters left ear: 136.18 avg.

Sorry to resurrect an old post. This is an interesting topic which I think bears further exploration. On the NFATALK database there is a definite trend that the large for caliber suppressor host combinations yield better performance at the ear with a trade off in performance at the muzzle. For instance, the mystic and 338 suppressors do better at the ear on an AR platform with 223 than the 7.62 silencers, which do better than the dedicated 223 silencers. Greater volume and baffle design also seems to play a role with higher volume and monolithic and k baffles outperforming Mtype or omega baffles.

The above comparison was great. I wonder how it would have turned out if the 45 end cap had been used on the hybrid and the 30 end cap had been used on the omega? I bet they would have performed better at the right ear and worse at the muzzle. If you ever get those numbers, I would love to see them .

Personally, I think semiautomatic suppressed firearms would yield a better experience for the shooter if manufacturers paid less attention to dB at the muzzle and more attention to dB at the ear. A little more gas flow, a little less dwell time, and design elements to limit back flow when the action opens, could all prove beneficial.

[doubloon]

Interesting findings, mostly I use it to compare total NSR to 1 meter results.