I ran this mod on Friday at ConnectiCon in Hartford CT. The investigators got dynamite, located bad guys, blew hole in back wall and decided throwing sticks of dynamite would be fun. Well, a stick of dynamite went astray due to throw failure and landed next to the supply tent that conveniently had 2 barrels of gunpowder and 10 sticks of dynamite. The dynamite was 10 feet from the barrels so I ruled that they exploded. I had it vaporize the tent and 3 outlaws but not quite sure what the effect of on rest of camp would be. I did have 2 nearby investigators make luck roles and had them fly through the air stunned.
My question is how do you calculate a barrel of gunpowder?