I am huge fan of the 7mmSTW, with the 160gr Accubonds.
My Sendero loves them! 1 ragged hole @ 100, and I wouldn't hesitate to shoot Elk at 750+ yards....if I had the right glass on top, which I currently don't. But will someday soon.
I would imagine the 7mm Weatherby would be a good one too.
And I see no reason why a 7mm Rem Mag wouldn't be able to do it either @ 500 yards with some 160gr Accubonds.