BTW this was my experience using a 45 cal TC omega with 45 cal Hornady SST 195 grain sabot(40cal projectile) using three 50 grain triple7 pellets. That load chronograph at 2394fps, I rounded up to 2400. A guy at the range let me use his chronograph once and only once. When the smoke cloud, firey junk and sabot hit his chronograph trap, he wasn't very happy...lol
That sounds similar to what happend when I tried to chrongraph my buddies 50 BMG . I thought it would be safe to pull the chrony to the side while he shot the first sighter and the blast from the muzzle brake blew the whole thing over and broke it.