Different powders react differently. Are you noticing a lot of carbon in the open breech, or if you shoot a scope, under the scope? I just decided that for my open breech rifles like my Wolverine, Staghorn, Whites, and Black Diamond rifles, I would just stick to the powders that were working. Although in my Knight Disc (closed breech) I did have excellent luck with the 209 powder and would shoot that again.