I, uh…
Might’ve been the guy that fired a nuclear-level hand load out of a snub-nosed .500 S&W. It had a big ol’ brake on the end.
At an indoor range.
The flash reached into both lanes on either side of me.
Ever heard a busy indoor range go instantly silent? That’ll do it.
FWIW, it was my buddy’s gun and his loads, so I didn’t exactly *know* that was going to happen; after I emptied the cylinder, I did apologize to the shooters next to me (and my buddy offered them a chance to shoot it; one took him up for a single round…)..
A little different than a brake on a rifle, though. I generally don’t shoot rifles at indoor ranges.