I'd also head over to Advance and go to Parks & Sons and buy a couple of pounds of Goex FFF black powder...Start with 80grs and move up in 5 grains until you find what that gun likes...Most Knights that I sight in will come in at either 80 or 85 grs...That load will do all that needs doing to a deer...
I don't know what they are charging for a pound, it was $13-14 last year...Their number is on the Goex website...