I have the same gun in .454 with a Weigand mount and a Ultradot Matchdot. I am not a fan of the balance, so I am in the process of going back to irons with the upgraded Hi-viz.

I had good luck with the accuracy of the factory Federal Fusion 260gr as well as handloads with the Hornady 250gr XTP with a upper end charge of Titegroup. I don’t remember the load off of the top of my head, but it had low extreme spreads. Both loads mentioned above are mild loading. They are much closer to heavy .45 Colt or .44 Mag ballistics than full-tilt .454 loads. No clue as to how they handle flesh though.