7MM Rem. Mag. - How Loud is It?

[oldillini]

Based upon my experience, I did not notice either the recoil nor noise level when I took my bull elk couple weeks ago. The 7 mag did its job. I do have a Limbsaver pad on mine. Reduced recoil noticeably, probably in range of 20-25%.

 

[Paul7]

At 65 years old my hearing is what it is. While I don't get out hunting much anymore I never wore hearing protection when I was hunting. I always wear hearing protection on the range. Here nor there as when hunting we are generally exposed to the sound of a single (maybe two) shot. That's it, it's not like shot after shot. Most will tell you that when hunting they never really hear the shot and granted, that does not mean no damage was done. However, speaking on my own behalf and having hunted with 30-06 and 7mm Remington Magnum I never really noticed much if any difference in the bang. I have noticed that for me, a Ruger M77 in 7mm Rem Mag does seem to kick me noticeably harder but that is about it.

In the end since hunting, unlike being on the range for a hundred shots is most often a matter of a single shot or maybe two so how much would the difference between a 30-06 and a 7mm Rem Mag really matter?

Ron

I find it easy to wear a pair of low profile earmuffs around my neck and slip them on before taking a shot. I'm at the point where I'd rather miss an animal than damage my hearing, there's lots of game animals but you only have one set of ears.

 

[Reloadron]

I find it easy to wear a pair of low profile earmuffs around my neck and slip them on before taking a shot. I'm at the point where I'd rather miss an animal than damage my hearing, there's lots of game animals but you only have one set of ears.

I can agree Paul but years ago the acoustical protectors were not as convenient as today's. They were large and bulky. Also, the nice electronic ones didn't exist. So when hunting hearing protection really wasn't much of an option.

Ron

 

[Clark]

I have a 7mmRemMag reamer, have built 3 rifles; Rem 700, VZ24, Mosin Nagant, and I have 3 factory rifles: Browning 1885, Rem 700, Ruger #1.

I studied Acoustics EE360 Under Rubens A. Siegelman in 1976 with the Kinsler book at the University of Washington.
http://www.sciencedirect.com/science/article/pii/0161734681901012
http://www.amazon.com/Fundamentals-Acoustics-Lawrence-E-Kinsler/dp/0471847895

Rubens was a German Jew physicist professor that fled Hitler, like Einstein.
The Disney parody of Einstein was Professor von Duck.
Some students used to call Rubens, professor von Duck.

Since then I have done some more math and testing and altering rifle designs and...

Companies used to pay me to design things and test things, and I was really grumpy about having controlled tests, so that if the test were repeated by someone else, they would get the same results.

That is not going to happen with gunshot volume level measurements. The best we can hope for is one time set up relative tests.

The threshold of gunshot bang is when escapement gas reaches supersonic speeds, slows down to subsonic and propagates a wave from the surface of the gas ball. That threshold is ~ one atmosphere above ambient. The 7mmRM has a muzzle pressure of ~10,000 psi = ~ 680 atmospheres. So it is going to make noise.
All guns with supersonic gas make the same noise level at high frequency. That is 2 atmospheres at the peak of the wave and 0 atmospheres [cavitation] at the trough of the wave. A lower frequencies there is roll off that is function of the wave length and the size of the gas ball at propagation. Cannons have more bass note quality.

So to the extent your measurement emphasises bass notes, you will get a difference in loudness levels.

A good approximation to compare rifle noise is to multiply the grains of powder burned times the muzzle pressure that Quickload predicts.

That, to a first order, will be proportional to the size of the supersonic gas ball.
Doing this, you will see that the 7mmRM is very loud compared to non magnums.

 

[gspn]

I have a 7mmRemMag reamer, have built 3 rifles; Rem 700, VZ24, Mosin Nagant, and I have 3 factory rifles: Browning 1885, Rem 700, Ruger #1.

I studied Acoustics EE360 Under Rubens A. Siegelman in 1976 with the Kinsler book at the University of Washington.
http://www.sciencedirect.com/science/article/pii/0161734681901012
http://www.amazon.com/Fundamentals-Acoustics-Lawrence-E-Kinsler/dp/0471847895

Rubens was a German Jew physicist professor that fled Hitler, like Einstein.
The Disney parody of Einstein was Professor von Duck.
Some students used to call Rubens, professor von Duck.

Since then I have done some more math and testing and altering rifle designs and...

Companies used to pay me to design things and test things, and I was really grumpy about having controlled tests, so that if the test were repeated by someone else, they would get the same results.

That is not going to happen with gunshot volume level measurements. The best we can hope for is one time set up relative tests.

The threshold of gunshot bang is when escapement gas reaches supersonic speeds, slows down to subsonic and propagates a wave from the surface of the gas ball. That threshold is ~ one atmosphere above ambient. The 7mmRM has a muzzle pressure of ~10,000 psi = ~ 680 atmospheres. So it is going to make noise.
All guns with supersonic gas make the same noise level at high frequency. That is 2 atmospheres at the peak of the wave and 0 atmospheres [cavitation] at the trough of the wave. A lower frequencies there is roll off that is function of the wave length and the size of the gas ball at propagation. Cannons have more bass note quality.

So to the extent your measurement emphasises bass notes, you will get a difference in loudness levels.

A good approximation to compare rifle noise is to multiply the grains of powder burned times the muzzle pressure that Quickload predicts.

That, to a first order, will be proportional to the size of the supersonic gas ball.
Doing this, you will see that the 7mmRM is very loud compared to non magnums.

That is no doubt, the smartest thing I will read all week.

 

[Gtscotty]

That's interesting, thanks for posting Clark!