I'm very happy with my .50 cal. load: 90 grains of granular 777, with the Remington Kleanbore primer. My favorite bullet is a Winchester Platinum 265 gr. hollow point sabot. Unfortunately, I can't find these anymore. I don't fire many shots without cleaning--usually four or five shots at the range to check my sight, then I clean it and go hunting. Cleaning at the range consists of a few shots of Windex down the bore, followed by a bottle of water. When I get home, I use the dish rinser (that spray thingy) with hot water for a few minutes, then patches until clean (usually the first patch is clean). I dry and heat the barrell with my wife's hair dryer, and if I'm putting it away for the season, I coat the hot barrell with Bore Butter. Never had a problem with the crud ring. By the way, I also use Bore Butter on the breech plug threads before reinstalling it.
I think the crud ring problem largely occurs with 777 pellets and standard 209 primers, not the reduced-powe ones designed for muzzle loaders.