I have two a 50cal and a 54cal. So far the 50 cal likes 80grlooseT7 with the green MMP sabots and about any bullet in the 240gr range.
The 54 likes 100gr. loose T7 with the red MMP sabots and T/c mag express sabots and a 230gr HP XTP or 230gr Speer gold dot.

I did a search here and other ML sites whenI started looking for a load to start out with for the 50. Turned up loads all over the board from 80 to 120 gr of powders from T7 to Gorex. bullets from PRB to 460gr conicals.

Al