This M855 spec round conceals seven grains of steel beneath its tip’s gilding metal jacket. That’s what earns it the name “penetrator,” as its steel content strengthens the bullet for more reliable penetration through barriers. The penetrator bullet is designed to pierce 1/8” of steel or 15” to 20” of soft tissue at 2,000 feet, making it an effective selection for self-defense when the situation merits.
This round’s case is a little ugly, but it’s not a reload. What you’re seeing is the discoloration that results from the annealing process, which makes the brass more malleable so it can expand to seal the chamber during ignition and go on to offer value at the reloading press. Winchester just declined to buff it out. This ammo is Boxer primed and non-corrosive, and its bullet is absolutely, positively magnetic.