i've got a white mountian, its made for sabots the barrels a fast twist i think 1/20 I've used pyrodex 90 grains (loose powder) and 300xtp's and harvester crushed rib sabots...shoots good....black powder would be good too . 90 grain powder and a saboted 45 cal bullet should be good for hunting .....to be sure you'd have to try 80-85-90 grains and see what gives you best groups...i had 4 inch groups at 50 yards not great be good enough to kill a deer ..ed