Semi - many say 1000# energy minimum for whitetail though many dead deer might argue otherwise. I killed a deer with the 10mm/200 XTP this year and was not impressed. I used 100gr Pyrodex RS and maybe that was the problem. At 25yds, the bullet went out with the same size hole it went in; no expansion. That was literally a heart shot so not much to slow it down. The deer went 100yds, fortunately across open field. I love the flat trajectory of the bullet and it would probably be great at 100yds but I'll be going heavier from here on out. Maybe a 200 all lead would be better?