That's a hard question to answer. Muzzleloader bore size differs even between the same model. If the Knight bullets loaded with moderate pressure you could try Harvester black sabots (50 cal/.452" bullet). If you present bullets were difficult to load you could use the Harvester Crush Rib sabot also in black. These are the ones that I use in my .50s and they work well. MPM also makes a variety of sabots for that bullet but not having used them I cannot comment.