The MOST accurate load I ever fired from a muzzleloader was a .500" round ball, .015" patch, and 90 grains of DuPont FFg in a slow-twist .50-caliber Bill Large barrel. On a calm day, this load would shoot five shots into 1" or slightly less at 100 yards. In my muzzleloaders, the max. magnum loads are generally less accurate than wht the gun is capable of with less powder!! But this is not always true of modern weapons!!
But, I will tell you I don't understand why people say it kicks so bad. In my opionion, it kicks less than a shotgun shooting slugs and it surely kicks less than a magnum calibur high powered rifle.
Actually, until we are talking calibers for African dangerous game, a shotgun firing slugs kicks MORE than a high-powered rifle...... A LOT more!!