Very corrosive! All Chinese military is, only the later commercial ammo was 'claimed' to be non-corrosive. My brother ruined a mini 14 using their 'non-corrosive' .223! Don't take any chances and clean.
My surefire does this with Federals, but only if I yank the trigger as fast as possible. (almost a bump fire). Otherwise with Federals, it works perfectly. My Saiga won't run at all with the Winchester crap, though, so it's not the mags fault.