I'm no authority or anything like that, but I would think the #9 would work fine. After all, it's just plastic. Once it cools, I would think a few good strokes with the brass brush an you would be ready to go. Let's see what the rest of the family has to say, but I don't think it should be a problem. I know someone on this forum posted about a product out to help prevent plastic fowling in the bore. It may have been Quick, not sure. It was quite a while back. Good Luck.