I knew a guy who worked for a gunsmith. He test fired a customers .300 RUM rifle with the customers reloads. The rifle detonated and blew off most of his hand. He had other minor injuries, but survived. The rifle was completely destroyed. The scope was found on top of a house over 100 feet away. It turned out that the reload was really light load of IMR 4831. I don't know if it was an intentional reduced load or was done accidently. Either way, he should not have fired some one else's reloads. I won't use any powder in my .300 RUM that leaves a lot space in my case.