To make things clear right off of the bat: 1.) I absolutely love my g19 EXO and bought it brand new on 18 JUN 11 2.) I have put approx 600 rounds through it and thoroughly clean it obsessively after each use 3.) It is my primary off-duty carry weapon that goes with me everywhere I go in my super awesome, super comfortable Crossbreed Super Tuck 4.) When I pulled it out yesterday, this is what I found It looks like rust but I have no idea how it could be possible. I'm at a loss for words and I'm not sure what I should do as far as trying to clean it w/o possibly making it worse. (I am a Hoppe's #9 guy). Anyone experience anything like this specifically on the slide of their EXO version pistol? Comments, suggestion??? THANKS!