150 gr .277 LRAB, launched out of a 270 WSM Montana. Shot this bull at about 100 yards IIRC. Bull barely reacted to being shot and trotted off with the herd. Never found a single drop of blood luckily still found him piled up about 150 yards away.
In all honesty i didn't perform a bullet CSI so I can't tell you what happened, even with help I didn't get the meat and head back to the truck until 2am.