I will add my Zimbabwe 2 bond to the fray, (the govt. took all of real money away). I have watched buffalo hit with .450-400 & 400 J, there is a notiable difference thump, both make a buff dead if hit in the right place. The .404J is really a pleasant rifle to shoot and with the 300grn bullet. I believe it is pretty much a equal to the .375 H&H. My wife just passed her Zimbabwe PH shooting test, her rifle CZ. 404J shooting her last two shots (accuracy test) from the prone position (.300 grn.). She would much rather shoot her .404 J than her .375 H&H. There is a real difference when you hit a gong with a .404J. Not sure about all of the ballistic stuff, but even with my ears I know the difference between a "whack" & a "WHUUCK"!