SW M&P 15 MOA Problem

[trubilt1]

I just bought a brand new SW M&P 15 MOA rifle. I love the rifle, but the receiver has a terrible blemish. It looks like some kind of a film on it, but it won't come off. It looks terrible. Anyone have any ideas what this might be or any ideas how to get it off?

[SwatDawg15]

Post a picture. If you dont know how, you can email it to me, and I'll post it for you.

[Gump]

is it purple?

[PlatoCATM]

Rub some dirt on it.
Seriously, if it is functioning reliably, don't worry about it. If you have the balls you could always grab a rattle can and cover whatever character marks it has acquired.