Sight in at 50. Then check at 100, and also whatever you feel would be the longest shot you want to take. Adjust your 50 yd sight-in as needed to optimize your trajectory for your hunting situation.

Most slugs work out so 2-3" high at 50 is on, or up to 2-3" low at 100, depending on velocity.

If you are shooting newer sabots that run around 2000 fps, you may be able to stretch things a bit.