I heard it's remanufactured military surplus, where they've supposedly yanked the bullet, reprimered and/or put new powder in, and put'r back together. It's supposed to be non-corrosive, but from personal experience I know it's not the case. If what I heard was true, then they probably miss rounds frequently, leading to corrosive ammo still being present in the lots.
Regardless, I wouldn't count on it in any way to be non-corrosive.