Well I too find a "crud ring" with Pyrodex. What it amounts to is some nasty fowling. Unlike Triple Se7en it is not hard in nature. In fact with Pyrodex I would guess you get actually more fowling then with Triple Se7en, its just not noticed so bad until you clean the rifle.

As for the stuck cleaning patch, make sure you never run a clean drypatch down a dirty barrel. Use a damp patch of the "correct size" as one too large will be hard to work in the barrel and are more prone to sticking. Work the barrel in short strokes of approximately two inches, working your way down the barrel. Do not attempt to work the patch further until you can feel the area you are currently in, the patch moves smooth. If the patch does not, remove it and send down a second damp patch, again in short strokes. This is the best way I know of to keep from getting a stuck patch...