>> yeah. >> i believe that you looked into that as well. explain to people how it's possible that shooting a prop weapon could kill one person, could injure another. especially if there is not live ammunition necessarily involved in these prop weapons. >> so when we're dealing with a casing full of gunpowder, gun powder essentially explodes. it turns instantly from a solid to a gas. it creates a tremendous amount of pressure. when it's a blank, simply that pressure is released and some fire and noise with it. that pressure is capable of killing people. john eric hexom was killed by the pressure coming out of the gun, pushing a piece of his skull through his brain. in brandon lee's case, they were using what is called a dummy round which is different than a blank round. a dummy round has, for all external appearances, everything in common with live ammo except that it doesn't have gunpowder inside it.