Hi guys,
I remember reading a couple years ago that the vibrations from certain synthetic stocks exacerbated hearing damage. This sounds plausible and I would like to know more.

Has anyone heard any further about this?

Any info gratefully received.

Gabe

IMO, if proper fitting and functioning ear protection is used, hearing loss will be kept to a minimum, regardless af stock material.

Interesting matter; I've never heard about that, but I know that noise propagates inside the skull through the mastoid bone as well, so I wouldn't be surprised....

i saw an article in a magazine a few months back that did say just that. just another reason for walnut further did you know that highly figured walnut is even better than plain all the little black lines and swirls confuse the sound waves so they loose their energy before they can get to your ears Honest

I think wood stocks channel sound right into the cheekbone and from there, it goes right into your ear, possibly causing hearing loss.

Remember the old Injun trick of using a stick to hear the Pony soldiers coming? Isn't a wood stock similar?

I think the Hogue Overmolded stocks, with the rubber coating, might help with this.

Trouble with the Hogue and many other synthetics, is that they are hollow..I wonder if that would make matters worse?

quote:

Trouble with the Hogue and many other synthetics, is that they are hollow..I wonder if that would make matters worse?

You can go to a hardware store and get a can of that insulating foam that rapidly expannds to fill up whatever space you're trying to fill up.I've done this in a Butler Creek stock and it worked great.
One caveat. be sure to mask everything real good and treat the barreled action just as if you were glass bedding. Move fast because that stuff expands very very fast. It doesn't seem to affect the gun's weight by very much. I got my foam at Home depot.
Paul B.

Paul,

Thats something I already plan for my Hogue...At the moment you get a hollow "clunk" as you cycle the bolt and figure the foam will make things sound a bit more solid!

Regards,

Pete

You'll have to speak up. . . . what was that?

Like I always say "HUH would you repeat that"

Rad

I can chime in on this subject some.. having a medical background, I also worked in sales for several years in the otolyngology ( ENT.. Ears Nose Throat) Market place...

I have scrubbed in on quite a few surgeries where they were repairing granulation that had occured in the mastoid behind the ear...

Ths site may help understand the physiology and anatomy of the ear...http://education.yahoo.com/reference/gray/subjects/subject/230

But simply, the bone behind your earn picks up vibrations and those vibrations are what help your ear to hear... in some people that bone starts to granulate ( kinda like turning to sand) and it starts to absorb the vibrations without passing them on to the ear canal..like the difference between a metal bar passing on vibration and a sandbag, that won't...

there was a government study being conducted by the University of Montana, at the Hospitals in Billings and funded by the Federal Government that were studying this exact problem...

In a large number of cases studied, all patients had to be people who shot rifles and shotguns fairly often and had started getting hearing loss...

What was noticed was that the patients were loosing their hearing on their shooting side... but yet were wearing ear protection...

It was also found that almost all of those that were loosing hearing were users of synthetic stocks for most of their shooting...

Harmonics were tested on various stocks and materials they were made of...

what was found out, was that wood stocks ( walnut etc) actually absorb a fair amount of the harmonics during recoil and do NOT pass on a lot to the shooters cheek ( which underneath that side of your face is your mandible/jaw and your mastoid behind your ear)...

even better for absorbing most of the harmonic vibrations were laminated stocks.. they proved much better than even the wood stocks...

The Hogue Rubber stocks, because of their rubber coating were also absorbing much of the vibrations from recoil...are also an excellent alternative for a stock.. and were rated high..

worst were the synthetic stocks...

of course "synthetic" can mean a lot of different materials...kevlar and other materials that will absorb or dampen the harmonic vibrations upon recoil are much better than some of the cheaper stocks such as a Butler Creek...these low cost stocks actually pass almost 100 % of the harmonics and vibration from recoil right back down the stock and the shooter's cheek is right up against it...

What is happening, is that synthetic stocks are applying more of the harmonics to the mastoid than the normal parameters can stand over time..

this leads to minor cracks within the bone and degeneration.. when that happens, it can no long pass vibrations to the inner ear and your hearing declines...

for what it is worth also.. European designed stocks that are popular over there are actually better for preventing this problem than American designed stocks ( I am speaking of ergonomics here... check out the way CZ offers European style stocks and American style stocks.... the Euro ones are better as they keep the vibrations farther away from the mastoid....)

Too much vibration is what causes hearing loss..

When I was in the National Guard in the Medical Corp, I use to have to give hearing tests to pilots of Helicopters for their annual flight physicals...from their test results you could always tell which side of the helicopter their duty station was... the side that was closest to the engine, was the one that had the bad hearing once it went...

it doesn't mean you have to avoid synthetic stocks... just avoid the cheap ones if you shoot a lot, especially the bigger the caliber and the more the recoil...

Kevlar ones and Hogues are a good choice...

Laminate is still better...

Shooting lighter calibers is also a good way to keep your hearing...

over exposure to the vibrations is what makes you loose your hearing...cheap synthetics pass all that vibration right back to your mastoid...
hearing protection doesn't absorb the vibrations....all they do is block vibrations within the inner ear.. not the mastoid...

Thanks for such a comprehensive answer!

seafire,

very interesting. You do not happen to remember where this study was published?

Thanks a lot

Cashew

Searfire,

I believe this external transmission of sound via the mastoid bone is another reason why proper ear defenders (ie muffs or cans) are better than simple in-the-ear style plugs...

Regards,

Pete

Seafire--

Thanks for the explaination.....this may provide yet another reason to dump the cheaper synthetic stocks I have and don't like. Seems odd that sometimes you can not like something and not be able to put your finger on quite why....

Cheers,

Dan

Seafire - any correlation betwen the MAGNUM CALIBERS and hearing loss

Seafire,
Thanks for the info, do you know what journal that was published in and approximate year?

I guess I am glad my 416 Rigby is a CZ Euro wood stock then.

seafire2 ; Your Full of information .

It depends on the stock in question when it comes to synthetic materials as well as what wood is used to dampen transmission of harmonics .

I would think it's safe to assume that anyone who is or was in military service has significant hearing loss .

I know I do , how ever I have actually gained some of that loss Back . I just got tested a few months back and it's better now than it was 20 years ago !. The doctor says that's not possible but I'm living proof it ain't BS .

Another way I minimize what I hear when shooting is a Face ( Similar to a cheek pad only thinner ) pad and Ear plugs on a elastic strap when hunting . At the bench ear muffs hearing protection .

Shoot Straight Know Your Target . ...

time to figure out how to afix on of those white noise generators to my guns

how are the Weatherby Synthetic stocks? I have a Mark V synthetic blue steel 270 winchester.

Well, how much shooting are we talking about here? I'm familiar with the problem of physical vibrations affecting hearing, but how many shots would you have to take with a particular synthetic rifle to cause a problem? It would seem with the relative infrequency of shooting, you'd probably have other issues affecting your hearing.

I know this IS a problem for a lot of factory workers or heavy machinery operators who, while wearing comprehensive ear protection, still endure heavy vibrations which eventually damage their hearing. I'm just wondering if shooting is a real issue in this regard.

Either way, it's still nice to know.

Sorry I haven't revisited this for a few days...

I have a few questions about the study...

Well boys, can't answer that...

Actually I had the opportunity to sit down with the doctor that was leading the study over breakfast one morning, with a good friend of mine that knows him thru civic activities in Billings...

Since I had a background in audiology and could relate to a lot of what they were finding, the doctor really enjoyed explaining it to someone from outside of work, that understood it..

Got to speak with him for about 2 hours over this study... when I did so, the study was far from over...

The real key here is the ability of the stock to absorb the vibrations and harmonics during and immediately following recoil...the more the stock absorbs, the better it is on your ear's well being...

even with the best of hearing protection, if you have a cheap constructed synthetic stock on a loud boomer.. and you shoot that type of stuff a lot... you are still going to end up suffering hearing loss..

Scopes going bad due to recoil is no different effect on them via vibrations and repeated vibrations.. than the effect is going to have on your ear drums and mastoid if they are exposed to a lot of severe vibrations...

Stocks material and design are very very important.. and the more you shoot, especially the bigger the calibers, the more at risk your hearing well being is...

One of the scope companies advertises that their scopes are tested to 'survive' the recoil of 1000 firings of a 375 H & H.... well we all can relate to how much damage that would do to our shoulders... what makes anyone think that recoil with that stock up against your cheek isn't also going to be rocking your ear and mastoid on your shooting side..

if they say some rifles can produce enough recoil to "loosen filings" in your teeth, what effect do you think that vibration is going to have on your eardrum and mastoid once again?

This is another reason, why I load my cartridges with mid burn rate powders.. compared to the trendy slow burning powders...
like the thread on the 7 Rem Mag here..
I use 60 grains of IMR 4064 instead of 70 or 75 grains of another powder.. so I may sacrifice 100 fps MV or so... but I am also reducing the recoil of that round by at least 20% less powder.. which is transferring less vibration and harmnonics down my rifle stock to the side of my head...

With a 60 grain charge and a 150 grain bullet, I can get an MV of 2900 or so fps with that load... with a 40 grain charge of IMR 4198 or Rl 7, I can get 2700 fps with the same bullet, using 20 grains less powder.. not only have I substantially reduced recoil, I have also substantially reduced the vibrations and harmonics that are going to be transferred back to the shooter's face on his shooting side...

Even spent an afternoon shooting prairie dogs with a 22.250.. and after 200 to 300 rounds, you have a headache? Even with a varmint weight rifle with synthetic stock or laminate stock, you are still dealing with what they want to call 'shooter fatique'...actually, your body hurts and aches because of all the recoil vibrations you have been enduring in a row...

anyone think this doesn't effect your eardrum, your mandible and your mastoid??

kinda just like glass finally getting a crack in it.. slowly it degenerates...

hard to convince a lot of shooters, because it goes against the macho factor, and also goes against the "trendy' trend burning of more slower powders" and the trendy " a full case is always more accurate"....however, the less powder you burn, the less recoil.. the less vibrations to your head...

So you guys that know I am a big proponent of Blue Dot loads, or SR 4759, IMR 4198, and Rl 7 as powders.. especially in off season practice..
well now you know another reason why....

but very few shooters even have a clue about the effects of vibration on the mandible and the mastoid process, and how it leads to hearing loss..,. they just think if they wear "hearing protection" it will lead to prevention of the problem... it only prevents a part of it...

using lighter loads, lighter calibers and a good stock are just as inportant in hearing loss prevention as using ear plugs and hearing protection...

stock design and stock constuction also have a MAJOR contributing factor to hearing loss prevention also...

at 55 yrs old, my last hearing test results were equal to the results of the average 8 yr old...and I shoot a whole heck of a lot!

quote:

Originally posted by seafire2:
Kevlar ones and Hogues are a good choice...

Laminate is still better...

Thank you! I always liked the feel of wood more and have gone to laminates. Prevention of hearing loss is an added bonus!!