Noise level of a 9mm carbine vs 223 or 7.62x39 w/16in barrel

[W L Johnson]

What would you say the noise level of a 9mm carbine like the CX4 is vs the noise level of a 16in 223/5.56 or 7.62x39 in a house? Or for that matter, a 12ga?

 

[briansmithwins]

The 12 gage would be slightly less, in my experience.

9mmP is pretty high pressure, like 5.56 NATO or 7.62x39. Noise wise those 3 are all in the same ballpark, barring a brake amplifying the sound.

Pretty much any shooting indoors w/o hearing protection is going to cause hearing damage. If it's a once in a lifetime occurrence that's one thing. If you do that work everyday invest in a suppressor and electronic hearing protection. BSW

 

[Float Pilot]

Have fired all indoors and outdoors. The 9mm carbines are considerably less noisey than the others listed.

 

[Girodin]

My 9mm sub 2K seems to be notably less noisy than the various 5.56 and 7.62x39 carbines I have fired. I don't have the numbers but just based on observation I would imagine there is a big difference.

 

[rangerruck]

bigger around pipehole, plus a bullet proly traveling at a max of about 1500 fps from a 16 inch bbl. gotta be a lot quieter, than the other 2.
i would guess kinda like comparing a leather whip by 2 lion tamers, one is heavy slow, and weighted on the end, the other two are light , fast, and has small strip of leather on the end. this one should make a much higher , louder cracking sound.

 

[natman]

The 9mm has a much smaller powder capacity in relation to bore size than either of the rifle rounds mentioned. Plus it's loaded to lower pressure (35000 psi for 9mm, 45000 for 7.62x39, 55000 for 223). Plus it's loaded with faster powders for pistol use. All this combines to make a lot less unburned gas at the end of the 16" barrel, hence less noise.

 

[briansmithwins]

Having been in a room where a 9mm was fired (ND by a buddy) with no hearing protection I still believe that you're going to be hard pressed to tell the difference in sound levels between the calibers mentioned.

A decibel meter yes, ears no. After the 1st round your ears are already going to be ringing.

BSW

 

[jordan1948]

+1 on the 9mm. Much quieter than the others.

 

[rhinoh]

Haven't had the misfortune of discharging any indoors, outdoors there is no similarity. I own rifles in all 3 calibers- The 9mm is way quieter than the .223 or 7.63x39

 

[EdLaver]

I have a CX4 9mm that I have fired in a fun house type training setting and it wasnt very loud at all.