Bigcountry, that may end up being the route for me. I just got done tumbling 20 shell casingsof .50 last night for three hours (in corn cob), and they look almost clean.Some of the shells that I bulk purchased have some sort of a black lacquer smeared on them, the tumbler isn't talking it off, neither is the Nevr Dull polish unless you scrub at it for a long time. Looks like steel wool is destined for these particular shells.

Kindest Regards,

-Will in Maryland