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Suppressors speed of sound ?'s

krw

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Minuteman
Feb 28, 2004
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I know that say a F16 breaking the sound barrier is louder that a 22RF breaking the sound barrier. Even though a 9mm bullet is 2x+ bigger than a 22cal and a 45cal bullet is 4x+ bigger, is there any dicernable difference in these breaking the sound barrier? Also is there any difference in a Spitzer type bullet and a Flat Nose bullet same caliber breaking the sound barrier in relation to audibly telling a difference? Thanks!
 
I know that say a F16 breaking the sound barrier is louder that a 22RF breaking the sound barrier. Even though a 9mm bullet is 2x+ bigger than a 22cal and a 45cal bullet is 4x+ bigger, is there any dicernable difference in these breaking the sound barrier? Also is there any difference in a Spitzer type bullet and a Flat Nose bullet same caliber breaking the sound barrier in relation to audibly telling a difference? Thanks!

I doubt it's enough to make any difference your ears can detect.
 
Larger bullets can and do make more noise than smaller ones. A 9mm is louder than a .22LR at equivalent speed. Higher speeds make more noise as well.
As for flat point vs round nose it makes no difference. The shock wave moves depending on speed not shape. It moves backwards as the speed increases and there will be a shockwave at each end. Look up some spark photos on google and you'll see. Faster and or bigger= more noise, smaller and or slower= less noise. Its all relative however. I can hear the difference between a 9mm and a .22LR but I can't tell the difference between a 6.5mm at 2900fps and a .30 cal at the same speed.....

Frank
 
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the shape of the flying object making the boom does effect how loud the boom is as shown here in Lockheed Martin's design for their new more quiet supersonic jet: https://www.cnet.com/news/supersonic-without-the-boom/ Is there enough difference in the shapes of various bullets of the same grain weight and velocity to muffle the sonic boom of some rounds and leave the boom louder on other rounds? I don't know
 
Larger bullets can and do make more noise than smaller ones. A 9mm is louder than a .22LR at equivalent speed. Higher speeds make more noise as well.
As for flat point vs round nose it makes no difference. The shock wave moves depending on speed not shape. It moves backwards as the speed increases and there will be a shockwave at each end. Look up some spark photos on google and you'll see. Faster and or bigger= more noise, smaller and or slower= less noise. Its all relative however. I can hear the difference between a 9mm and a .22LR but I can't tell the difference between a 6.5mm at 2900fps and a .30 cal at the same speed.....

Frank
Watch the video, skip to around the 5 minute mark. Bullet shape absolutely plays a role in supersonic shockwaves and speed.

 
A 9mm is louder than a .22LR at equivalent speed. Higher speeds make more noise as well.
In your analysis, 9mm vs .22, I've been wondering if this is due to the much larger powder charge required to get the 9, which has a heavier bullet, to a comparable speed. Much more gas at the muzzle.

Higher speeds = more noise is very evident shooting subsonic rimfire. You can tell which rounds are faster out of the same box of ammo just by listening.