The acronym JHP stands for Jacketed Hollow-Point, a variety of ammunition found commonly in handguns and sub-machine guns, in which the round has a "pit" or "dent" in the tip of the round. On contact with target, the pressure on the peet causes lead from the back of the round to blossom out into the front, creating a mushroom shape with a larger soft-tissue damage to round caliber ration. JHP ammunition is forbidden in warfare by the Hague Convention, but is often used in police and personal-defense weapons, because of the lack of tendency for overpenetration, resulting in less chance of civilian casualties.
"Personally, I prefer to use JHP rounds, but have you ever seen a dummy hit with fragmenting ammo? Ouch."
by Wade R. December 21, 2005