I agree with Misty. That is definitely unsafe.
A bunch of us got together and bought 80 acres out in the coungtry. We made some backstops. After awhile a club member who lived about 3/4 mile down range came and said we were shooting his roof. Turned out tha shots were ricocheting off the berm, not burrowing into it. The NRA came out and explained what we had to do. There was a VERY LARGE assessment of all members. From the pictures in the video, there is no way the guy's trench is safe. There will be ricochets. .50 BMG rounds will cause the slopes to subside.
I belong to another club that has a hill about 60 feet high as the backstop. Twice I have seen rounds go over that hill, even though nobody is allowed to shoot there except classified High Power competitors.
Most of the noise from a supersonic projectile comes from the sonic boom, not the gun going off. That means that the noise reaching Misty's house comes from only 200 feet uprange. It will be VERY LOUD. I don't even like to drive the golf cart around our Sporting Clays club without hearing protection, even though most shots are (a) farther than 200 feet away, (b) not fired in the direction I am, and (c) a 12 gauge is nowhere near as noisy as a .50 BMG.
Incidentally, when hunting in Ohio, it is illegall to shoot within 500 feet of a house, whether or not you are shooting in that direction. And that's with a shotgun. Further, I am faniliar with most or all of the ranges on the North Coast. There is only one where full auto fire is allowed (they shoot .223 and .45 ACP) and NONE where a .50 BMG is allowed, slow, rapid, or full auto fire.
I think the best bet would be a noise ordnance. Don't rthey have them in Florida and can't someone get a dB meter?
