WellI personally would get some Triple Se7en 2f and a pound of Pyrodex RS in loose powder. Get a powder measure and measure your own. One of those powders will work good for you. Your wallet will thank you also. Also get some 240 & 300 grain XTP's and some Harvester crushed rib sabots in bulk. The black sabots are .452 the green are .430 so make sure you match the bullet diameter to the sabot. These should work good.

Using a powder measure dump 100 grains of either of those two powders and have fun. You might have to swab between shots or every other shot, but I think you will more then pleased with the accuracy.

You might also want to try some 250 & 300 grain Shockwaves. The trouble with recommending what projectile will shoot out of your rifle is, they are all different. What works in one might not work in another. But the ones mentioned are known performers in most rifles...