If it's an original Disc that uses the flat orange primer holders, you will first have to get a Disc Extreme conversion and add a bare 209 primer conversion kit. If it's a Disc Extreme that uses the red cylindrical primer holders, the bare 209 conversion is all that's needed. Knight still sells both or you can sometimes find them cheaper on the auction sites.
http://www.knightrifles.com/product...g-supplies/muzzleloader-conversion-kits/
