It's not going to hurt anything.
You can try cleaning it with regular gun cleaning supplies and if you really want to go crazy, get yourself some Flitz polish at an auto parts store, put some on a bore mop that fits snugly in the die and run it in a cordless drill for a few seconds. It'll smooth as a babies...
In any case, it won't hurt anything the way it is.
Still happily answering to the call-sign Peetza.
You do not HAVE a soul. You ARE a soul. You HAVE a body.
He is no fool who gives what he can not keep to gain what he can not lose.
-Jim Eliott, paraphrasing Philip Henry.