[TML] [OT] One for Gun Safty

[Anthony Jackson]

Michael Jenkins wrote:

> Aren't pistols generally subsonic?

Depends on the caliber. .22LR, 9mm, 10mm, magnums, etc, are supersonic. 
.22 short, .25, .32, .38, .380, .45 are subsonic.
> 
> Adding a very small lag for acceleration of the round, it's possible
> he'd hear something very briefly. I hadn't actually looked this up
> before ... I was just goin' for funny. Depending on nerve reaction
> times, it's also possible that the bullet will make it into his skull
> cavity before he hears the noise.

Certainly before it reaches the conscious mind (about a half second).

However, the sound _will_ reach his eardrum before the bullet. The 
bullet pushes the air out of the barrel, and that air will reach his 
eardrum (as a shockwave) before the bullet, even if the bullet is 
supersonic.