I have 5 boxes marked "PMC 5.56 MM BALL M193" and the box also states "Made to US Military Specifications". The cases have the head stamp "PMC 223 Remington". I understand that it is not a good idea to shoot 5.56 in a .223 chambered rifle, but these are a little confusing. I suspect these all come off the same line and get put in different boxes as these are in a real nifty camoflage box, but I would think that if these were, indeed really M193 ball, they would be stamped accordingly with a NATO symbol. I have never seen ball ammo with the civilian designation like this, or .308 Winchester instead of "WCC 69". Does anyone have any knowledge on these, and if they are safe to use in a .223 bolt action rifle?
