Winchester's PDX1 Defender ammunition is specifically engineered for modern sporting rifles, utilizing Split Core Technology (SCT) to achieve an optimal balance of expansion, retained weight, and penetration for personal defense situations. The protected hollow point design ensures reliable feeding and initiates rapid expansion upon impact. The SCT bullet features a front lead core that delivers quick impact shock, while the rear lead core is bonded to the jacket to ensure maximum weight retention and critical penetration. This design results in a bullet that expands up to 1.5 times its original diameter, creating significant terminal performance. Additionally, this ammunition features low-flash propellant for low-light scenarios and comes in a nickel-plated brass case.