Mike
Why do you buff it? I just use the cheapest spray paint I can find, and give them a good spraying.
Fleener
A lot of my unmentionable bullets will make a decent splash and leave a thin scale of lead, copper, slag... whatever it is I just swipe it off with the flapper wheel and hit it with El Cheapo white paint.
I may have to just spray it and see how it holds up.
Mike