I have a brand new Glock 27 that's I've had for a month or 2 now and just got done cleaning it because I suspected a development of rust. I've done countless research on the internet, but am still not 100% sure if I was actually looking at rust on my Glock 27. I've owned a used Glock 22 and never seen rust before. It appeared to be light/thin rust, and was the color of rust too. I also saw the same thing on my brand new Mossberg 500 (which is much newer). I'm thinking it was rust because I didn't put gun oil on the exterior of the Glock's slide and not on the exterior of the barrel, ect. of the Mossberg. Now that seems like a dumb move, and I agree, but the reason I didn't put oil on these parts is because the guns' manuals said not to put oil on these parts. I wish I had a picture, but I don't. I've seen rust before, so I was confused. I could only see the faint color of rust when I shined these various gun parts in the light. Can rust indeed be so faint as this? Some internet sights claim I was looking at the Glock's faint Copper Finish, but that doesn't seem so to me, being that the Glock is so new. Also, if there is rust on the exterior surface of the Glock/Mossberg, what is the best way of removing/servicing rust without causing cosmetic damage? Someone please verify these findings to me. It boggles my mind because these guns are so F'in New (I have shot them by the way, but no more than 50 rounds through each)! I'm in the Navy, and have cleaned guns alot before, but when I did that I simply used CLP and didn't really care about the appearance of the guns that much. I'm using regular cleaners and oils for my personal guns, and care about their appearance this time. I used only "Bore Scrubber" as an overall cleaner before. Could that be it? I have a "Gun Scrubber" now, so I think I should have been using that for overall cleanliness. Both the above and "Gun Oil" I have are from the company "Birchwood" that I bought in the local range and gun stores.