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owejia
04-05-2019, 10:47 AM
Shooting handguns in a three sided concrete range, bottom and two sides, about 10' wide and 6' tall would the bullet be effected by the sound waves from bouncing off the floor and walls, or is the bullet ahead of the sound waves?

osteodoc08
04-05-2019, 11:03 AM
The way I understand it, it depends on bullet speed. Super sonic vs subsonic. I've never known sound waves to affect my shooting. Its a parabolic shape around the projectile. Now if we go from super sonic to sub sonic in flight, there is a transition and can cause instability. Interesting question.

redhawk0
04-05-2019, 11:21 AM
I would say there is no effect. The sonic (hyper, super, or sub) wave would be way behind the bullet. The conical shape of the shock wave is primarily behind the bullet and not in front of the bullet. By the time the "shock wave" would hit the wall and bounce back...the bullet has already long passed by that reflected shock wave.

redhawk

Omega
04-05-2019, 12:00 PM
Here is a good video about bullet shockwaves that may answer your questions:

https://www.youtube.com/watch?v=BPwdlEgLn5Q

RED BEAR
04-05-2019, 01:36 PM
I would say i doubt there is any effect.

marek313
04-05-2019, 03:01 PM
I dont have PHD in physics but based on what i learned in college I dont think that would affect trajectory.

My opposing argument would be that if that was true people shooting outside would see tighter groups which i dont think is the case and i never experienced that.

tazman
04-05-2019, 10:32 PM
Supersonic--no effect. The sound waves are behind the bullet.
Subsonic--Little to none. probably not noticeable or measurable even if it is there. The sound waves would travel only slightly faster than the bullet and would have little if any time to bounce back and effect the bullet. By the time the sound waves bounced off a solid wall, they would have lost a lot of their power in any case.
At the distance you are shooting, assuming 25 yards, the sound waves would only be able to effect the bullet during the last 20 feet of the shot, at most. This amounts to about .025 seconds.
Basically, no noticeable effect.

str8wal
04-06-2019, 10:51 AM
Any sonic waves would be in the wake of the bullet, much like a boat in water, and wouldn't have any effect on the path, IMO

gwpercle
04-07-2019, 04:50 PM
Based on the armed robber firing 4 shots , at me , inside our 8' x 8' office kitchen , I did not notice any of the bullets being affected by the sound waves....my hearing was affected , but not the bullets flight .
Just not enough distance for the sound to act on the boolits . This is from actual observation, not theory .
Gary

owejia
04-07-2019, 06:31 PM
At 68 degrees fahrenheit at sea level sound travels 1125 ft/sec, so if bullet velocity is slower, then the sound waves would be all around the bullet in flight. The reason was pondering this, my bullet catcher is about 30 ft past the three sided concrete drive into my basement, where I test my loads in handguns. Gary you are correct about your hearing being affected in a small confined space, shot a varmint out of an open door in my tractor cab using a 7mm mag. Most of the rifle was sticking out the cab door and I thought the noise would not be too bad, boy was I wrong, made me lose my equilibrium and took several seconds before regaining it. Never crossed my mind that the sound would also travel backwards and bounce around the cab. That is the reason my night stand guns are loaded with low velocity rounds, the flash and sound will disorient you for a few seconds when fired in a small confined space.

tazman
04-07-2019, 09:05 PM
Another thought about the situation. T
For a handgun, the sound waves would be coming from nearly all directions simultaneously even after bouncing from the walls, or at least very close to it.
Probably all boolit movement due to sound would be offset by the sound from the opposing sides. Even if it all came from one side, it would have very little time to move the boolit before impact.
Much less than a long range rifle shot and a steady wind.

charlie b
04-09-2019, 03:10 PM
There is a big difference between sound waves and shock waves from supersonic projectiles. Sound waves will have so little influence you'd have to have some very sophisticated instruments to measure any differences. Supersonic projectiles are ahead of any reflected shock waves so no difference there.

gwpercle
04-09-2019, 05:08 PM
At 68 degrees fahrenheit at sea level sound travels 1125 ft/sec, so if bullet velocity is slower, then the sound waves would be all around the bullet in flight. The reason was pondering this, my bullet catcher is about 30 ft past the three sided concrete drive into my basement, where I test my loads in handguns. Gary you are correct about your hearing being affected in a small confined space, shot a varmint out of an open door in my tractor cab using a 7mm mag. Most of the rifle was sticking out the cab door and I thought the noise would not be too bad, boy was I wrong, made me lose my equilibrium and took several seconds before regaining it. Never crossed my mind that the sound would also travel backwards and bounce around the cab. That is the reason my night stand guns are loaded with low velocity rounds, the flash and sound will disorient you for a few seconds when fired in a small confined space.
It sure seems louder when you are on the muzzel end of the gun ...but after the third shot you barely hear it .

9.3X62AL
04-09-2019, 06:12 PM
I enjoyed the video that Omega posted VERY MUCH!

str8wal
04-09-2019, 10:17 PM
At 68 degrees fahrenheit at sea level sound travels 1125 ft/sec, so if bullet velocity is slower, then the sound waves would be all around the bullet in flight.

Sound might be all around the bullet, but does it affect the bullet's flight? Highly unlikely.

owejia
04-10-2019, 09:20 AM
Very good video Omega. The reason the question was asked, was curious if the bullet would be affected by the sound waves if the bullet was not centered in the concrete channel of my shooting range. If the sound waves on the short side or from the bottom would have any affect on the bullet flight would be so small wouldn't distort the flight path of the bullet.

tazman
04-10-2019, 07:16 PM
What happened to 35 Remington's post about my usage of affect/effect?
I thought it was humorous as well as educational.