James B You hit it exactly!!,

Guys, you can't compare bullets of the same weight between calibers and expect the same results!! It's the SD and bullet construction that counts when you are trying to get decent penetration for game animials.

The SD is the length of the bullet in relation to the diameter, so a 100 grain 6mm is a lot longer that a 100 grain bullet in say, 30 cal..

Drilling Man