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Old August 1, 2015, 12:35 AM   #26
Theohazard
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One thing I've noticed is that historical accounts of a silencer's quietness are often greatly exaggerated. Modern accounts are often also exaggerated, but now we have modern measuring equipment that can very accurately measure the silencer's decibel level.

One example is the Delisle Carbine, which was an integrally-suppressed bolt-action .45 ACP carbine used by the British in WWII. Legend has it that it was one of the quietest suppressed firearms ever built, and at the time is was metered at 85 dB, which is far quieter than any modern silencer.

But that number doesn't make any sense, most firing pins alone are far louder than 85 dB; I've seen a test done by Major Malfunction that showed the Model 700's firing pin is 105 dB when dry-fired. This discrepancy was cleared up when Stalking Rhino Industries got ahold of a Delisle Carbine and tested it, and it metered around 128 dB. So it was actually about the same as most modern detachable .45 suppressors that are much smaller.

It's pretty clear that that the 1940s technology used to measure the Delisle Carbine was simply inaccurate. And, like most subjective accounts of silencers' quietness, the witness accounts were also unreliable and innaccurate.
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Old August 1, 2015, 05:07 AM   #27
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Old August 1, 2015, 10:24 AM   #28
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It's pretty clear that that the 1940s technology used to measure the Delisle Carbine was simply inaccurate.
We have much "better" (more precise, more accurate) ways to measure many things today than they did in the 40s, or back at the turn of the 20th century.

However, we don't always draw the right conclusions from modern measurements. Pressure is one area where things can get very confusing, but that is a subject for another thread.

All "silencers" work on the same general principle. The chambers & baffles, etc., provide extra area for the gas to occupy, slowing down the bulk of the gas, delaying its exit from the muzzle, slightly. This reduces the muzzle blast. The delay is very short, to our human senses, but it's enough to keep the gas from all coming out in one big bang.

Think of a tire, and the fairly loud hiss you get if you cut off the valve stem, versus the loud BANG of a blowout. Both vent the pressure, but make much different sounds, due to the time spread of the gas release.

Different designs do it different methods, with differing degrees of success, but the general principle remains the same. By changing the rate the bulk of the gas exits the muzzle after the bullet, the sound is changed.
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Old August 1, 2015, 10:27 AM   #29
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I think they're well worth it if you're in a position to spend the money. I don't own one yet, but I've shot a number of them. They just make shooting a lot more enjoyable. Less noise, less recoil, less flash. If they were unregulated as muzzle brakes are, I think I'd have one for every gun - or at least every caliber - I shoot. They'd be great for hunting too so you didn't have to wear hearing protection. Many of them are hearing safe for one or two shots, and that's usually all you need for hunting.

One thing that sticks out to me is the Tikka I shot suppressed. It was in .300 Win Mag. A very light rifle, I'd be surprised if it had weighed 7 or 8 pounds with the scope and suppressor. With the Silencerco Harvester, it was really sweet to shoot. I was amazed at the recoil. I had always heard .300 Win Mag recoil was fairly sharp, and I expected a kick out of the rifle. Instead I got a slow, smooth push. I'd honestly rate it to kick about as hard as our very heavy R700 in .308
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Old August 1, 2015, 04:05 PM   #30
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Do silencers work? Are they worth it?
Yes & Yes

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Old August 1, 2015, 08:24 PM   #31
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I can't speak for anyone else...but I get a silly ass grin every time I shoot my suppressed guns!
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Old August 2, 2015, 12:10 AM   #32
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They work extremely well, this one is hearing safe without ears.

http://youtu.be/WkHjZQZ7dpQ
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Old August 2, 2015, 02:11 AM   #33
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Originally Posted by HKGuns
They work extremely well, this one is hearing safe without ears.
No, it's not. If you shoot that without hearing protection, you will permanently damage your hearing fairly quickly. It might take a while for that damage to become noticable, but that doesn't mean it isn't happening. Your Octane 45 is about 130 dB at best; that's louder than a jackhammer and loud enough to easily damage your hearing.

No silencer is medically hearing safe. Repeated exposure to noises as low as 85 dB can cause hearing damage. Here's a good link from the American Hearing Research Foundation:

http://american-hearing.org/disorder...-hearing-loss/

"Habitual exposure to noise above 85 dB will cause a gradual hearing loss in a significant number of individuals, and louder noises will accelerate this damage. [...] The highest permissible noise exposure for the unprotected ear is 115 dB for 15 minutes per day."

In contrast, the quietest .22 silencers on the market rarely get a shot down below 115 dB. Most pistol silencers are between 125 and 130 dB. Most rifle silencers are between 133 and 138 dB.

Silencers definitely make a huge difference, that's why I own three of them and I plan to buy more. But claiming they're "hearing safe" is incorrect and irresponsible. The industry bases their claims of a silencer being "hearing safe" on a misinterpretation of OSHA rules, and that claim is disingenuous at best.
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Old August 2, 2015, 06:37 AM   #34
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No, it's not. If you shoot that without hearing protection, you will permanently damage your hearing fairly quickly. It might take a while for that damage to become noticable, but that doesn't mean it isn't happening. Your Octane 45 is about 130 dB at best; that's louder than a jackhammer and loud enough to easily damage your hearing.
I suppose "constant" exposure to anything over a whisper will eventually cause you to lose hearing.

I run and Im exposed to jackhamers, and a lot of other "loud" things at work on a daily basis, and a hundred rounds of even super sonic ammo through my my 9mm Glocks/Evo-9, are quieter and easier on my ears than just 30 seconds or so, of running or standing next to a jack hammer and/or its compressor. Even .223's through my M4-2000 are quieter.

For me, I consider things that dont immediately impact my hearing, to be "hearing safe". Not that they are over time, but if they dont cause me to lose, or reduce my hearing for a couple of days after, Id say they are "safer". A unsurpressed .22, or even an air rifle in some cases, will leave my ears ringing loudly, and my hearing muffled, and for a couple of days. I dont get that with the suppressed guns.
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Old August 2, 2015, 08:50 AM   #35
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Originally Posted by AK103K
I suppose "constant" exposure to anything over a whisper will eventually cause you to lose hearing.
According to most experts, the threshold is about 85 to 90 dB, which is a lot louder than a whisper.

Quote:
Originally Posted by AK103K
I run and Im exposed to jackhamers, and a lot of other "loud" things at work on a daily basis, and a hundred rounds of even super sonic ammo through my my 9mm Glocks/Evo-9, are quieter and easier on my ears than just 30 seconds or so, of running or standing next to a jack hammer and/or its compressor. Even .223's through my M4-2000 are quieter.
It's possible that it's easier on your ears, but without objective scientific measurement you really don't have any way to know that for sure. Simply guessing based on which one hurts less isn't a very accurate measurement.

Every source I can find measured a jackhammer at 130 dB or less, and some measure it as low as 100 dB. Obviously this variance has to do with the differences in measuring equipment and differences in the jackhammers themselves, but considering your M4-2000 meters around 135 dB, I think it's safe to say that the jackhammer is probably quieter from a decibel standpoint.

Now, the jackhammer is a deeper and more constant noise than the gunfire, so that's probably why it sounds quieter to you. Also, because the jackhammer is a more constant noise than the gunfire, it might take less time to produce damage even though it's a quieter sound. But either way, both of those are hurting your hearing.

Quote:
Originally Posted by AK103K
For me, I consider things that dont immediately impact my hearing, to be "hearing safe". Not that they are over time, but if they dont cause me to lose, or reduce my hearing for a couple of days after, Id say they are "safer". A unsurpressed .22, or even an air rifle in some cases, will leave my ears ringing loudly, and my hearing muffled, and for a couple of days. I dont get that with the suppressed guns.
Just because your suppressed guns don't cause your ears to ring and don't cause your hearing to reduce noticably, that doesn't mean they're safe on your ears. When you shoot your suppressed guns -- especially your .223 with the M4-2000 -- you're subjecting your ears to a decibel level that's well over the limit for permanent hearing loss. That loss might not be noticable to you, and it might be minor enough that you're willing to ignore it in order to enjoy the convenience of not wearing hearing protection, but medical science tell us that it is happening.
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Old August 2, 2015, 09:16 AM   #36
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Im not debating the science, only what I personally experience. Certain things are loud enough to cause my ears to hurt and deaden my hearing, so far, suppressed firearms are not one of them.

Im sure my IPod's, the constant roar of a heavy construction environment, loud equipment, and heavy tools, etc, are doing or have done, more damage to my ears, than the suppressed firearms I shoot.

I do know that I "have" to wear ear plugs with even the smallest caliber guns, when shooting without a suppressor, yet I have no discomfort and/or deadening of my hearing, even after extended range sessions, with rifle caliber guns that are suppressed.

Like the usual ballistics arguments, I think the problem with throwing paper "numbers" around is, things tend to get silly, and hairs split, over things that really dont mean a lot, except in the perfect world of numbers.

Even though I do shoot a lot, and a small portion of that is suppressed shooting, I dont find its as much of a cause to worry, as what I encounter in my daily activities. I wear ear plugs at work, and almost always when I shoot things without a suppressor. I dont normally wear them when I do use the suppressor, as one of the main reasons for them, is to allow me to do so.
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Old August 2, 2015, 10:44 AM   #37
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They do reduce the report from all loads.
But it is when you match the gun, load and suppressor, That you get great results.

If you match 22cal subsonic bullets to you suppressed rig. They are pretty quite.
Same with 300 Black out. load those big fatties running around 1000 fps in your gun and they are pretty quite.
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Old August 2, 2015, 02:53 PM   #38
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I guess I'll just change my name to Mr. Irresponsible, regardless of what the numbers say and most of those numbers are not measured at your ears. I find it very easy to shoot that combination without hearing protection.

Either way, settle down, no reason for you to get all worked up into a lather over it.
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Old August 2, 2015, 03:00 PM   #39
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Either way, settle down, no reason for you to get all worked up into a lather over it.
The way I see it you decide what to do with your ears but posters like Theohazard who clearly know a lot about suppressor performance and its affect on users, give you the facts so that you can make a fully informed decision.

I don't see that as getting all worked up, I see that as doing you a massive favour....

You may feel differently.
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Old August 2, 2015, 05:24 PM   #40
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Originally Posted by HKGuns
I guess I'll just change my name to Mr. Irresponsible, regardless of what the numbers say and most of those numbers are not measured at your ears. I find it very easy to shoot that combination without hearing protection.
I apologize if I offended you, but my statement was simply a fact: Your silencer is not "hearing safe", and if someone follows your advice they will get hearing damage. That damage might take a while to be noticable, but it's still happening.

Those numbers are measured at the muzzle of the firearm, but the decibel readings at the ear are no more than a few decibels different. No matter which way you measure it, your Octane 45 is well above the threshold for permanent hearing damage and is far from being "hearing safe", no matter what your subjective experience might try to tell you.

Quote:
Originally Posted by HKGuns
Either way, settle down, no reason for you to get all worked up into a lather over it.
Like James said, I'm not worked up at all, I'm simply trying to inform you that your can is not actually "hearing safe".

If you choose to keep shooting without hearing protection, that's fine; I'll admit that sometimes I don't wear hearing protection when I shoot my Octane 9 outdoors. But if someone decides to not wear hearing protection, don't you think it's better if they know the potential risks involved?

This is a popular public gun forum, it's important for us to not spread bad information that could potentially lead to unexpected hearing loss.
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Old August 2, 2015, 07:33 PM   #41
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None of my Cans are "hearing safe" i would describe them as "hearing tolerable"
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Old August 2, 2015, 07:53 PM   #42
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Hearing tolerable. That's about right.

When I shoot 147 grain subs through the can on my Uzi, I can discern the sound of the bolt going back and fourth.
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Old August 2, 2015, 08:06 PM   #43
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When I shoot rabbits out in the garden with my .223's at 50 yards, I can hear them "pop". And boy do they POP!

You dont hear that pop, without a can on the gun. At 50 yards, you dont get much of a "crack" either. Not enough time in flight I guess.
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Old August 2, 2015, 08:30 PM   #44
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They are a lot of fun. Trying to rationalize the cost and expense isn't any more difficult than most other emotional firearms purchases. Most firearm purchases are emotional purchases where the rationality is based in hopeful paranoia of being able to one day justify the arms. I wish they were more commonly accepted for hunting in various states, because that is probably the ONE absolutely most rational and beneficial use for suppressors. But everyone without experience with suppressors (including other shooters and hunters) all scoff at the idea of not having a .308 in a short deer stalker barrel go off right next to your 8 year old kid you are taking hunting for the first time.

Just buy one and have fun. I suggest a .22LR suppressor of decent quality that you can service yourself. AAC Element or Silencerco Sparrow, and a Ruger MkIII with a threaded barrel is a ton of fun. You can pretty much forget additional hearing protection with either of those, but a bunch of folks will cringe at that comment. I do think that centerfire suppressors still require hearing protection, but it's not needed with high quality rimfire cans.


Just buy one and have some fun.
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Old August 2, 2015, 10:17 PM   #45
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"Do silencers work? Are they worth it?"
Uncle Same sure seems to think so, in more ways than one (both insists on his own best men having them, and insists on ruining the lives of his citizens over them out of fear)

"Hearing tolerable"
Put it this way; many of my guns, it's uncomfortably loud to drop the slide/bolt under the mere recoil spring pressure with your head in shooting position. They're cycling much faster/harder than that in practice, to say nothing of the still hundreds of PSI venting from the end of the suppressor. All the can does is drop it from the 'explosives' noise range down to the 'air tools' noise range. All it means is now hearing protection is sufficient (that's right; some guns can't be made truly hearing safe with hearing protection, simply because your face/skull itself isn't a good enough earmuff, and no one wants to shoot with a ground-crew helmet on)

I see a recurring thread among the folks who claim it's no biggie or is totally safe in their estimation; they almost uniformly are already exposed to dangerous sound levels regularly (our jack-hammer and earbud examples are themselves excellent examples of this). Your ears acclimate; that's not to say that they become protected/resilient, but you get used to your ears being continually damaged, and your sensitivity goes away. Leave for a secluded vacation of a few weeks, and that loud environment will become intolerable, at least for a day or so. I hear the same stuff about shooting without ear protection unsuppressed all the time from the guys who drive rivets in the hangars all day.

Yeah, I imagine a braked AR probably is more comfortable than running an air hammer six inches from your face inside an echoing beer can for ten hours ... I said hours. ...HOURS!

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Old August 2, 2015, 10:23 PM   #46
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Originally Posted by Sharkbite
None of my Cans are "hearing safe" i would describe them as "hearing tolerable"
Perfect! I'm going to steal that for future use, just so you know .
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Old August 2, 2015, 10:56 PM   #47
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Are they hearing "Safe"? Not according to the experts, but I doubt the experts are going to claim you will damage your hearing just as fast with a can as without. They are worth every penny IMO.
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Old August 3, 2015, 12:19 AM   #48
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Are they "Hearing Safe"? No. But they are "safe-er"

Bottom line is, life is not hearing safe.

I had a documented high frequency hearing loss before I turned 21. Thank you Uncle Sam.

I spent years working industrial safety. Yearly physicals including the booth audio tests. Baseline readjusted several times over the years. Always wear hearing protection working or shooting. Or mowing the lawn.

Age damages your hearing, but everything we add to that just makes it happen sooner.

Audio tests have shown the majority of drivers have a (detectable) hearing loss in their left ear (right ear for Englishmen ). From driving with the window down.

Gunshots (and other loud noises) DAMAGE your hearing. it comes back, but never as good as it was before. We don't notice the reduced ability, until it reaches certain points. And by that time, its too late.
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Old August 3, 2015, 01:12 AM   #49
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Are they "Hearing Safe"? No. But they are "safe-er"

Bottom line is, life is not hearing safe.
I agree 100%. I hope nobody misconstrued my comments to mean that I think they're useless for hearing protection. Shooting a gun with a silencer might damage your hearing, but it's still a LOT better for your hearing than shooting without one. And there are definitely a lot of other things in our lives that also damage our hearing, the key is to understand those risks so you can take the appropriate precautions if you so desire. My bottom line is this: If someone decides to not wear hearing protection when shooting suppressed, that's fine; I just hope that decision isn't made out of ignorance.

I love shooting suppressed because it's extremely quiet when combined with foam earplugs. And if I'm in a situation where I'm not wearing hearing protection, I can shoot a few suppressed rounds off and not worry that I'm hurting my hearing too much. So I definitely think that silencers are worth it, that's why I've already started saving up for my fourth one.
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Old August 3, 2015, 09:36 AM   #50
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The Decibel scale is not straight arithmetic progression.
Sound power level (volume) is a base 10 logarithmic progression. 3dB = 2x or 1/2 the sound energy depending upon whether the sound is going up or down in value.

That is different than sound pressure level as that is a base 20 logarithmic progression with 6dB making a 2x or 1/2 change in sound pressure level.

The problem comes in when you try and calculate sound reduction by simply subtracting one value from another. With logarithms, addition = multiplication and subtraction = division.
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