I stopped by My local academy and picked up some winchester 5.56 FMJ ammo to test fire My newly built AR and after I got home I noticed the red stuff around the primer. It looks a lot like the same stuff that is around the primer on some known corrosive 7.62x39 ammo I have. My question is, does winchester make ANY corrosive ammo and if not whats the red stuff? Also is there any more issues with the corrosive ammo in an AR than say the AK, witch is basicly shoot the hell out of it and just clean the rifle real good.