I've taken 3 elk with a 325 gr cast slug at the velocities you mention. All were exits & I'm sure the 285 gr slug would have done the same. That 325 gr bullet, made from the correct alloy will take anything we have here in the states unless you get in a hurry or take a risky shot.
If you're impatient or a risky shot taker, use a different bullet. There's a lot of good one's out there.

Dick