Bullet and powder recommendations

I have a .50 cal Traditions Pursuit Ambush that I am taking to Kansas for a late muzzleloader hunt. In the early season hunt I shot 250 grain Barnes spit-fire sabots with 2- 50grain IMR White Hots. My guide recommended stepping up to 3 pellets since the shots can be up to 200 yards or more. Is my gun OK to shoot 150 grains? Any other load recommendations?

The rifle can handle 150 grains of a black powder comparable (I have a Traditions flintlock .50cal and have fired a few 150 grain black powder loads behind a patched ball) - but - if you are shooting a bullet, either "buttered" soft lead or high tech sabot you are likely to get better ballistic performance with 100 grains. Consider that the Minie ball (of French Capt. Claude-Étienne Minié fame) at .58 cal and over 450 grains of heavy, soft lead was most accurate with a 60 grain black powder charge (or sometimes less) and still had an effective range of 300 yards and functional range of up to 1,000 yards. There is such a thing as too much "punch" for the projectile to spin up and remain accurate.

Compare your accuracy at 100 yards, with the bullet you plan to use, using 50 grains of powder, 100 and 150. You might be surprised.