Sweets is a favorite of mine too. Removes everything save for a bad first impression. I use a straight nitro solvent, Balistol, or Eds Red if I'm not attacking metal fouling specifically.
If you're just blasting with surplus a slightly frosted bore isn't the worst thing in the world, though it'll still collect gilding metal. I cast my own bullets, however, so my bores needs to be bright and sharp.