I have been using a barrell polisher with ceramic cones (green and orange) to clean up casting. I pop a bit of pumice powder in to clean up to a matt state but find I still have to file and paper all the pieces to a 600 grit finish first to get rid of that casting skin before they can be barrelled to a high enough standard. Can anyone suggest a coarser media to save me a stage. Ideally I would just like to get rid of casting sprue and any mould lines and then leave the barrel to get on with the rest so I can do more of the fun stuff! Any suggestions welcomed - Thanks.