Ok so I just found one sub that most likely can kill someone from internal bleeding...
Link to Article
So I am not sure about the pressure required to pop lets say your kidneys but I am pretty sure that this sub can produce it. //content.invisioncic.com/y282845/emoticons/eek.gif.771b7a90cf45cabdc554ff1121c21c4a.gif//content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif//content.invisioncic.com/y282845/emoticons/eek.gif.771b7a90cf45cabdc554ff1121c21c4a.gif now imagine this sub with the cone from the first post... I bet that could kill people in the battle field, or at least send enough pressure to make their ears bleed...