I have taken quite a bit of game with a .280. A 140 Accubond pushed by IMR 4350 would be a good place to start.

I have used a 160 grain pill on larger game such as elk, kudu, et. For the 160 load I have not been completely happy with the Barnes bullets and have settled on the old standby Nosler Partition.

Mostly I just load the 140 grain bullet and use it for nearly everything.