My father in law took a really nice buck Saturday morning witha 6MM-284, using the Sierra 85 gr. HPBT. This bullet continues to amaze me - on an animal this big, it blew a fist size hole through the ribs and one lung before coming completely apart in the other lung. Deer was on the ground in less than two seconds. At a muzzle velocity of about 3750, and 100 yard impact velocity had to be pretty high. This is the fourth buck we have taken with this bullet - all rib shots - all one shot kills.