Re: Supersonic crack with suppressor
Absolutely, positively YES! But you're sort of asking from the wrong end, or at least that's what I get from your question. I'm still waiting for my paperwork to clear on my first suppressor, so I can't shed too much on the firer's perspective. I've used several suppresors with supersonic ammo, and they all moderated the noise at the firing point quite well. The sonic crack was still audible, but nothing too loud in most cases.
As for that crack itself, yes, you hear a very distinct difference when the bullet goes by, depending on the speed of that bullet as it passes. Spend some time in the pits at any highpower range, and you'll understand exactly what I'm saying. When pulling the target, the shooter's bullets will pass directly over your head, usually 2-3 ft above your position. The crack produced by a bullet's passage when fired from 200 yards away is distinctly sharper than what you'll hear from that same rifle when the shooter moves back to 600 or 1,000 yards. This is not to be confused with the "Thump" of the rifle being fired, and the two sounds are each very audible, and quite different. The difference from the pits when a suppressor is involved is that you still hear the crack of the bullet passing, but not the thump of the rifle being fired.