lol those mortars can be tricky... lol I had something like that happen this fourth but not because of anything stupid someone did... but because I guess the powder wasnt packed very well at all. SO me and like 5 of my friends are standing in a pretty close vicinity of the mortar and I light one and everyone backs away about 10-15 feet waiting for it to shoot straight up into the sky.. well we hear it go but don't see it shoot up... it kind of like pops out of the cannon i would say no more than 10 feet and then Just explodes... and well you know how big those things can blow? Yeah we all got like burnt and hit with shrapnel.... was crazy stupid but awesome at the same time.