If as everyone is saying the barrels havn't been degreased well enough. I don't think after 8 coats the first time and then 6 again the next, that your barrels will come out looking great. If they arn't properly cleaned and degreased i can never get a consistent blue. You should know right away, that something isn't right.

That said, i don't have a clue to why your blue is rubbing off.