So I got this Inert 25mm shell for a few bucks, and it's filthy. It's got rust around the core, some awful green-black stuff on the driving band and I don't even know what on the case. I know fine-ought steel wool works wonders, but I want to both limit effort and damage to the brass and copper. Fellow /k/ommandos, how do?
Also, that's a middle school art project I've kept, in the background. I may have autism.