CCI CB 22 Shorts out of my grandfather’s Winchester Model 1906 HAVE TO be hearing safe. They’re rated at 710fps, and 1906 is a pump. Plus, they are so short I can fit 16 rounds in the tube magazine +1 in the chamber for 17 rounds in an old pump that slam fires.
I would bet they are even hearing safe out of my 6.5” barrel Heritage Rough Rider pistol. It is pretty much just the primer propellant pushing the 29gr bullet.
Last edited by AdioSS; 01-10-2020 at 10:08 AM.
I don’t agree. I think there is a big difference in danger between going to the range once a week to shoot .380 acp and going once a week to shoot .327 federal. My ears are pretty trashed from a lifetime of both shooting and music performance, and I will say that I no longer shoot magnum cartridges indoors. A cylinder or two of .357 really gets my tinnitus going, while .380, all .38 and .45acp are no problem. 9mm+P is fatiguing; standard 9mm is right on the edge for me.Originally Posted by Nephrology
”But in the end all of these ideas just manufacture new criminals when the problem isn't a lack of criminals.” -JRB
I'm always skeptical of NRR--it's just a single number. It doesn't describe frequency at all. Just glancing at the back of my Leightnings' packaging, the average attenuation between 500mHz and 2000mHz--which would cover the peak of "small-arms" fire--ranges from 29.4db to 32.4db. Remember also that the decibel rating system isn't linear, it's based on orders of magnitude. Hence why the numbers for different calibers are so close, and why hearing protection with just slightly better stats gives much better apparent noise reduction.
That said, I would caution that you don't need to hear the noise to actually damage your hearing. Hence why I think using "work-grade" earpro is dumb. And you know those classic boomers that just crank down their hearing aids to shoot? Yeah, they're wrecking what's left of their hearing in short order. I know guys that have noticeably lost hearing doing that.
But, at the end of the day, I'm not worried. I wear decent stuff, I don't do stupid things. I figure if Givens and Jedlinski aren't going deaf standing around for a couple hundred thousand rounds a year, then I won't either, presuming I keep taking precautions. And, of course, super-ditto on avoiding indoor ranges and enclosed outdoor ranges.
It astonishes me just how careless people are with their earpro, tho. Once I really started paying attention to it, I realized most of the people I shoot with have poorly-fit hearing protection. We're talking visible gaps caused by eyeglasses and eyepro. Hell, I know one old moron that uses a pair of over-the-ear radio headphones as "hearing protection". Fucker is half-deaf. It would be fine, because I hate him anyway, but now he's much louder whenever I have to listen to him.
ME EE here with a speciality in acoustics, speech and signal processing.If you want to read something mildly disturbing, check out this article, and the formula for determining the actual reduction of sound from the printed NRR:
https://www.ssusa.org/articles/2019/...ction-ratings/
Put simply, the higher the NRR number, the more effective it will be at reducing noise. But, the NRR does not measure the amount of decibels being reduced. To figure that out, subtract 7 from the NRR and divide by 2. For example, if your hearing protection has a 33 NRR, the actual amount of noise reduction you will experience is 13 decibels (33-7=26, 26/2=13). So, if you are at a place where 100-decibel noise is the norm, with 33 NRR hearing protection on, your noise level will be attenuated to 87 decibels.
.25 ACP – 155.0 dB
.32 LONG – 152.4 dB
.32 ACP – 153.5 dB
.380 – 157.7 dB
9mm – 159.8 dB
.38 S&W – 153.5 dB
.38 Spl – 156.3 dB
.357 Magnum – 164.3 dB
.40 S&W – 156.5 dB
.41 Magnum – 163.2 dB
.44 S&W Magnum – 164.5 dB
.44 Spl – 155.9 dB
.45 ACP – 157.0 dB
.45 COLT – 154.7 dB
12 Gauge Shotgun – 155 dB
.22 Pistol or Rifle – 140 dB
M-16 – 160 dB
So, if you have those howard leight pros, you’re getting a true 13 db; add some foam plugs, and it’s another 12-13db. Call it 26db. Now look at, say, the .357 magnum. The only saving grace is that the duration is so short.
Bottom line, if you are not doubling up, especially indoors, you are fucking up.
This is pretty much spot on.
I like this post also.
Apples to oranges; I wouldn't consider .357 (or any other magnum pistol cartridges) to be in the same family as duty calibers (9mm, .40, .45).
Personally don't notice a big difference in noise from 9mm +P vs standard pressure but I mostly shoot outdoors. Have obviously never done any measurements.
Well, since I own a db meter, I’ll see about taking care of the measurement thing. I can tell you that .45acp indoors is less sound pressure than 9mm indoors.
”But in the end all of these ideas just manufacture new criminals when the problem isn't a lack of criminals.” -JRB
It’s pressure and supersonic that makes it louder, or at least appears to be louder. 45acp is actually quieter then 9mm because lower pressure and the standard load is subsonic.
147g 9mm is quieter then 115g. Longer barrels are quieter too.
Some good advice in the thread already regarding doubling up with quality hearing protection. Always double up when shooting indoors, for most shooting use muffs with a high NRR rating, and if possibly use the type that allow installation of gel cups that seal around the stems of your shooting glasses.
Personally, I perceive more concussive blast from a 45 than a 9mm. But based on measurement, 9mm is louder than 45. Revolvers are definitely louder than auto loaders, and short barrels can be much louder than longer ones. That's one reason I tend to shoot and use full size guns with long barrels. I shoot 45 mostly, and have just started shooting some 38 Super again after years without one. When I shoot my rifle it is always with a suppressor.
I have hearing damage and tinnitus, and I often wonder if I am further damaging my hearing by continuing to shoot at all. I don't plan to stop shooting any time soon, but I always have that concern hanging over me.
One last thought -- it was a .44 Special revolver fired outdoors to my left that caused most of the damage to my ears. So it's not just magnums or shooting indoors that you have to worry about.
Here's an interesting briefing from Larson Davis Laboratories focusing on sound pressure, suppressors, barrel length: http://www.larsondavis.com/ContentSt...d_Briefing.pdf
Among other things, they say a ballistic crack of a bullet is not a source of hearing damage as it's downrange and follows the bullet, unless the sound reflects off an object and back at the shooter.
Most importantly, "As was to be expected, the bore pressure at the instant of bullet uncorking correlated almost perfectly with the non-suppressed sound pressure level (dBA)." I take this to be the single most critical aspect. Reduce the pressure at uncorking - lower pressure round, suppressor, longer barrel - to reduce hearing effects.
The context is MIL-STD-1474D Department of Defense Design Criteria Standard Noise Limits 1997.
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