Use what you already use except use a fixed blade head instead of a mechanical if you do use a mechanical. Most adult elk archers usually use an arrow weight 400 grains or more.

People every year kill elk with as little as 20 - 30 pounds of KE. Some are kids with light weight arrows on their first elk hunting trip, some are women with similar set ups just because they can't pull much weight, and some are the traditionlists with heavy arrows. But, one thing these three groups usually have in common are good, sharp, cut to tip two or three blade heads.

They key is to realize your limitations and stick to them and match up your heads to your other equipment.