We just received the Bushmaster Patrolman and am confused regarding the uppers receivers finish.  
There are spots that appear to be flat, as if flat black spray paint was just shot in only some areas...cant tell if it is a poor finish or some type of protective coating.  Tried Hopps with no success and don't want to damage it if it needs to be returned.  
So the question is:   is this a protective coating from the factory (if so what do I use to remove it) or is it just a piss poor finish?
Any help would be greatly appreciated

I'd say it's a cosmetic flaw. Call the Bushmaster customer service number and talk to them about it,

You shouldn't have anything on the finish but oil.

.
.

Thanks!