Why suppress .308 or 7.62x51 guns?

strangenh

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Yeah, it matters - it's about a 75% drop in perceived volume. Dradian's numbers are correct with regard to how a person experiences the (auditory) effect of sound intensity. 20db is two doublings in perceived intensity, so if x=y*2*2, then y=x/4. (That's not how dbs work for energy measurement, but it's how human hearing perception apparently works with regard to loud noise.)

Think of it this way, would you shoot a .308 with lightweight, low-profile 20db earmuffs? Maybe or maybe not? How about if the report already had a 20db drop?
 

JRT

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I shoot 308 suppressed because it's hearing safe from a 16 inch barrel bolt gun, I hate hunting with earpro. There is a lot of work being done with subsonic 308 at the moment, I just listened to a podcast and there is new powders and loads being developed. Today's subsonic 308 is not very accurate because the loads are so small in the case. Today just shoot 300BLK, you get better ballistics from the modern projectiles and there is a ton of choices.
 

strangenh

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Suppressed 5.56x45 from an AR makes it sound like some kind of SciFi gun. It's fun. Also, a lot less loud.

Mostly fun.
 

edmorseiii

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That's not how sound works.... even a 6 db reduction is f***ing huge. 12.5% is a gross misrepresentation of the real life difference.

-Mike
OP likely already has his mind made up, wanted to confirm his opinion, doesn't get the db math, and would rather not try to understand it because then his opinion would be wrong.
 
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OP likely already has his mind made up, wanted to confirm his opinion, doesn't get the db math, and would rather not try to understand it because then his opinion would be wrong.
The state made my mind up for me. This is a purely academic thread.
 

RKG

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140 / 160 = 0.875, about a 12.5% noise reduction. Hearing safe is approximately 85dB.
Decibels are a ten log scale: you can't do a simple ratio like that. In fact, a 20 dB reduction in sound level means a 99% reduction in the sound pressure energy.

That said, a 140 dBA impulse sound at one meter is still damaging to a human's hearing.
 

RKG

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not exactly. Gunshot hearing safe is around 140 for limited exposure.

Also, Dbs are logarithmic not linear. 140db is significantly quiter than 160.

I think it is every 3db increase is double the volume. so 20 db would make it 6 times louder? I'm sure someone here can correct me.

edit: I had to look it up. It is every 10dbs sounds twice as loud. so 140 to 150 is double, then 150 to 160 is double again.
Not quite. You have to distinguish what something "sounds like" and the sound pressure energy that causes the sound. It is the sound pressure energy that is potentially damaging to one's hearing.

The human ear has a non-linear response to sound pressure level. It is estimated that 3 dB delta (either increase or decrease) is about the threshold of hearing a difference in perceived loudness -- even though a 3dB difference implies a doubling or halving of sound pressure level. A 10 dB delta is a ten times delta in sound pressure level; a 20 dB difference, a hundred fold delta.
 
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Because .308 has a lot of muzzle blast, literally skull rattling even with plugs in. People will complain about the blast from 5.56, but 5.56 is a peashooter compared to .308.
 
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Shoot a 300 AAC bolt gun with sub sonic ammo and a can and you can't wipe the smile off your face.

As others have said, it goes from single impulse damage to just don't do it a lot kind of damage. It's like the old hunter's response to almost every question about hearing loss from hunting, "What?"
 
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Shoot a 300 AAC bolt gun with sub sonic ammo and a can and you can't wipe the smile off your face.

As others have said, it goes from single impulse damage to just don't do it a lot kind of damage. It's like the old hunter's response to almost every question about hearing loss from hunting, "What?"
Agreed....

The best part if right around 15:15 on the video

View: https://youtu.be/z17UQUYzPhQ?t=903



Full disclosure: the can in the video is from my business.
 
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