Thread: Short barrels and decebels

Anybody done accurate testing of DB increase to the shooters ear of shorter barrels without muffelers on the end?

http://www.prep-blog.com/PDF/2-Gunfire-Noise.pdf

some data

Crap I cant open, "invalid value for registry" whatever that means. ?

Strange, it works for me

20" .223 160dB
18.5" .223 165dB

24" .30-06 160dB
18.5" .30-06 166dB

Gunfire Noise and Hearing
by William L. Kramer, Ph.D.

An estimated 60 million Americans own and use firearms for sporting purposes. Physicians and audiologists know that these people are at risk for noise-induced hearing loss and tinnitus, and often ask their patients if they are hunters. However, gunfire noise exposure from other recreational shooting far outweighs that experienced in hunting.In the U.S., only one-fourth of U.S. gun owners actually do any hunting. Based on a survey of 100 gun owners who did some hunting, an average of 200 shots were fired in practice or competition for every one shot fired at a game animal.
Since 1980, I have been collecting data about firearms and noise, and have measured the loudness of over 7,500 gunshots. Here is what I’ve learned: All gunfire noise ranged from 150 dB to 172 dB SPL. (There was one exception: The .22 rimfire cartridge as fired in a rifle barrel only measured up to 145 dB.) The average loudness for all shots fired was 158 dB. Black powder (antique/replica) firearms noise aver- aged about 3 dB less than conventional (modern, smokeless) powder firearms. Adding any kind of muzzle brake (a device to reduce recoil) added about 11 dB to the normal level. Short barrels were gener- ally louder than longer barrels. The head shadow effect caused the right and left ears to be exposed to different levels of noise. For example, a right-handed rifle shooter has his left ear closer to the muzzle, which means that his left ear gets more noise expo- sure (and damage). The right ear, which is in the “acoustic shadow” of the head, gets 3 to 7 dB less noise exposure.
I collected these data because of my inability to find a reliable and valid source for this type of infor- mation as it applied to firearms used by civilians in recreational and competitive shooting. While the peak
Figure 1 Noise levels for Various Firearms

BARREL AVERAGE RIFLES LENGTH dB SPL
.22 24" 135 rimfire 16" 145
.223 20" 160 18.5" 165
.30 - 0624"160 18.5" 166
decibel is the most frequently reported dimension of the noise, other characteristics, such as the duration and the frequency spectrum or pitch, are also impor- tant. What we think of as a loud “BOOM” may not be as damaging to our ears as a slightly less intense “crack.” An artillery gun (or howitzer) makes a huge “boom” which lasts longer than pistol sound and has most of its energy in the low frequencies. The rifle or pistol “crack” is shorter in duration with most of its energy in the mid to high frequencies. Research has shown that the rifle crack is more piercing and does more damage.
The hearing loss and tinnitus associated with gunfire noise tend to be of a higher-pitched nature. Further, hearing loss from excessive noise often damages hearing at 4,000 and 6,000 Hz with the pitch of any accompanying tinnitus located at the same 4,000 and 6,000 Hz. The tinnitus accompanying my hearing loss (brought on by gunfire before I learned about hearing protection) manifests itself in an inter- esting manner. When I have my hearing tested, I often don’t know if it’s a high-pitched tone coming through the earphones or if it’s the noise in my head. Because I have a high-frequency hearing loss, I don’t hear the telephone when it’s ringing; but my tinnitus makes me get up to answer the phone even when it’s not!
Hearing Protection
Shooters often ask, “What is the best type of hear- ing protection device (HPD)?” I respond by saying: “The one you will wear every time you shoot.” More specifically, there is no single “best” type of HPD anymore than there is a single best car, golf club, or camera. The situation determines what type of HPD needs to be used. Some of the factors involved include the type of firearm (rifle, pistol, or shotgun), weather conditions, tactical considerations (for military, police, or instructors), cost, and comfort. The last two are probably the deciding factors in

BARREL AVERAGE SHOTGUN LENGTH dB SPL
.410 Bore 28" 151.0 18.5" 157.3
20 Gauge 28"
22" 154.8
12 Gauge 26" 156.1 18.5" 161.5

BARREL AVERAGE PISTOLS LENGTH dB SPL
.22 LR 6.75" 151 4.00" 155 2.00" 160
9 mm 5.00"159 Luger 4.00" 163
.45 ACP 5.00" 158
All measurements were made using Bruel & Kjaer precision sound level meters and were made at the ear of the shooter. The sound pressure levels (dB SPL) were based on a minimum average of 10 shots for each type of ammo in each firearm and barrel length.
14 TinnitusToday/June 2002 American Tinnitus Association

So something tells me that 6 db difference on 30-06 is more than one would think?
Had to get a mates bike under some limit to be legal and tho only a few db 3-4 from memory it was about half the noise to the ear.

After If I recall 140db you are causing damage, tinnitus isnt fun when your trying to sleep.

I've got a meter we use at work. Might take it to nzda range on Sunday if anyone is feeling curious about with/without can on.

3db is about twice as loud and the closer the blast to your ear the more damage you till do , but both are not hearing safe

dB scale is logarithmic, 3dB = "twice as loud" from memory

the whole reason for short barrels though is to be able to use a "muffler" without having a stupidly long setup.

Also wouldnt the shorter the barrel be the higher muzzle pressure and more physical noise anyway. that would be more of a negitive effect than the 3 inchs closer to you

I dislike cans and wear hearing protection for all but close range shots.
I already have tinnitus and don't care to make it much worse.
Just thinking how short one could go on an efficient calibre like 308win without massive volume to the shooters ear increase.
I know the old mans rossi (cant remember if 16 or18 inch) is pretty antisocial (without muffeler)with the barnes load I made for it but I am using a relitivly slow powder for barrel length which results in a bit of flame thrower and a lot of Boom!

So your being picky of 135 to 165db? Get a can or get a 22 bro

Sound doubles every 3 db its not like money that doubles when multiplied by 2

Originally Posted by veitnamcam

I dislike cans and wear hearing protection for all but close range shots.
I already have tinnitus and don't care to make it much worse.
Just thinking how short one could go on an efficient calibre like 308win without massive volume to the shooters ear increase.
I know the old mans rossi (cant remember if 16 or18 inch) is pretty antisocial (without muffeler)with the barnes load I made for it but I am using a relitivly slow powder for barrel length which results in a bit of flame thrower and a lot of Boom!

Why the dislike for cans?