One of the things you should do is wipe the bore until a patch comes out clean. You should probably also get a scraper for the breech as there is a lot down there that a patch can just brush over. As for the lock, it might depend on the amount of shooting you did. If it wasn't much, you can probably get by without taking the lock off. Wipe it down with a black powder solvent and then wipe with an oily rag. If you can see a spot that is a nook or crevice, the black powder residue will already be there, so get in close. Maybe use an old toothbrush, or if you are mad at the wife or girlfriend, hers.
Wipe the inside of the bore with an oily patch. Before shooting the next time, run a patch soaked in alcohol down the bore to remove the oil or you may have a misfire. If your gun has a vent that is removable, take it out, clean it, and before you put it back in, use an anti-sieze compound on it so you can get it back out in the future.
Black powder is very corrosive, but if you clean well and soon after you shoot, you will never have a problem.
The Doc is out now. :hatsoff: