One that worked in 3 different muzzleloaders was using 100 grains of BlackMag3, Federal Fusion Muzzleloader primer,and the Hornady 250gr SST with the RED sabot.
I can tell you that with 7 different all copper bullets let it be Barnes,Knight, or T/C's Copper bullets you could have covered the holes with you hat. In some cases the only difference was the sabot itself but make a difference in loading and how they shot. The slower burning Shockey's Gold and the Goex Pinnacle shot lower of course. The fastest was BlackMag 3 with Triple 7 and BlackHorn 209 pretty close 2nd over all.
Physical things that I did to my Endeavor was free floated the barrel using a washer under the ramrod lugs, T/C's adjustable hinge pin,trigger job to give me 2lbs pull.
Justin