yeah it is 4.2 for some reason Ive always said 4 and a half? any way you've fired one? its awesome aint it. We did a traversing fire on a ridge at a firing range about dusk on a day it was kinda stormy, we were on the third traverse and was firing an HE round, I had just fired the round and it was maybe a second or a second and a half down range and it was struck by a lightning bolt and blew up!!!scared the living crap out of us. it was a long range shot so it seemed like the apc was about to flip when we fired it cause of the charge we had set on it, so when it blew so close.... we packed it in that day. True Story, I'll swear on a Bible!!