Posted on 01/03/2014 9:33:37 AM PST by LouAvul
I often see experienced shooters wearing only ear plugs for hearing protection. I usually double up with plugs and muffs, but when I'm shooting in extreme cold, sometimes it's uncomfortable (not being able to wear the type of head covering I might normally wear).
I'm headed to the range next week to break-in a couple of rifles, a CMP Garand w/CMP ammo and an unfired M1A w/factory ammo. The charts usually circulated say 140 dB at an unprotected ear causes instant damage. The M1A is a 308 at 156.2 dB and the Garand is 30-06 at 158.5 dB.
My plugs are rated at 31 dB. My understanding is that because these figures are logarithmic, I subtract 5 from the 31. The plugs actually only reduce the sound by 26 dB. That reduces the Garand, for example, to 132.5 dB.
Assuming one has the plugs inserted correctly, etc, and assuming one is shooting by himself, exposure to instantaneous sounds at 132.5 dB is safe.
After all, even with the addition of muffs, you only add 5 dB to the total hearing protection anyway.
Any Freeper's input on this subject?
Question: How does the sound power decrease with distance"? Answer: "April fool - The sound power does not decrease (drop) with distance from the sound source."
Levels of sound pressure and levels of sound intensity decrease equally with the distance from the sound source. Sound power or sound power level has nothing (!) to do with the distance from the sound source.
Thinking helps: A 100 watt light bulb has in 1 m and in 10 m distance really always the same 100 watts, which is emitted from the lamp all the time. Watts don't change with distance.
A frequent question: "Does the sound power depend on distance?" The clear answer is: "No, not really."
Based upon the above, I'm firing a 308 with a 24 inch barrel, the 24 inch distance doesn't really matter.
in the army plugs would always fall out, I wore muffs around the back of the neck so I could still get my helmet on.
“never, EVER take the OPROD out of an M60 if the charging handle is locked back”
Ask me how I know.
I only double up on an indoor range. Earpugs are fine outdoors especially for rifles.
Peltor headset. All you need.
For your rifles, the major sound impulse is going mostly forward and to the sides, not back at you.
Also, energy drops 6dB for every doubling of distance, whether it is light or sound. Spherical expansion of the energy, impossible for it to remain the same intensity if you stop and think about it.
Someone should ask the genius that wrote this, "Why can't I use a 100W bulb to read 100 feet away if as you imply, it is just as bright?"
Yeah, I have been surprised at the slap back from reflected sound more than a few times.
The sound level depends on what you are shooting and your attachments. Flash suppressors are different from a compensator.
A compensator redirects blast force and sound back towards the shooter. A compensator can increase the sound to more than 10-15db.
A 25dB NRR doesn't actually mean you subtract that from the outside noise. The recommendation is that you cut 5dB off of the NRR and apply that.
IOW, 165db - (25dB-5dB)=> 145dB exposure per shot.
That detail in the noise exposure guidelines is often missed.
The guy above who said that if you're indoors and somebody sets of a .454 Casull (or even a .44 mag, in my experience) you will be uncomfortable even with both kinds of protection was right. That's also very true with high power rifles like 30-06. The muzzle blast is pretty intense from a powerful gun of any sort.
On a lighter note, I always tell women shooters I use both plugs and pads. It takes them a while to figure that smart @$$ comment out.
Study compensator vs flash suppressor.
Smartest thing I ever did was have custom molded plugs made.
Block out everything, and are comfortable all day.
Granted this guy is local to me, but this webpage gives you an idea of what I’m talking about.
http://www.hearingprotectionservices.com/non-electronic/
In 1985 I attended National Gun Day in Louisville, Ky. Somebody was selling a M60 for $3500. In 1986 Reagan signed into law a stipulation that no machine gun manufactured after 1986 could be sold in America.
That same M60, today, sells for around $60,000. Reagan must have had a personal collection of machine guns.
Doesn't make sense. I can hear people shooting shotguns in fields that surround my area but I don't need ear protection.
OK, then I guess he was just saying the noise ratings are overstated. Has nothing to do with the logarithmic system.
But as I said, I just use the foam earplugs I get at Lowes in bulk when shooting and it seems quite adequate.
OK genius, show me where he stated either rifle will have a compensator or brake on it.
Last I saw, CMP M1 is stock unadorned bare muzzle. M1A comes with basic mil spec flash "hider".
The are arguing semantics. Being further away from the gun does not make the gun quieter, it is just as loud, but the energy delivered to your ear drops by square of the distance. Distance is very important, otherwise all that shooting in the middle east would have deafened all of us by now.
I wear plugs and muffs now... was just a plug man... but six months ago I damaged my left ear when a plug came out as I fired a .45 acp. I have high frequency Tinitus in my left ear. Be warned!
Is he sure? It’s very easy to confuse the two and there are many products that attempt to do both with various degrees of success. The two terms are frequently confused and or used (i.e. clip and magazine) even by knowledgeable shooters.
The only way to be sure is measure the db level and choose hearing protection accordingly.
Get a bigger hat. :)
You know those “custom molded” earplug that specialists charge you a ton of money for? You can make them yourself. Pretty much the same thing, for about $12-15 a set. Look for the do-it-yourself kits.
I wear them for 6+ hours at a time and forget they are on.
Put some electronic muffs like Leight or Peltor on over them with the volume turned up. Comfortable and you can still hear a little bit.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.