STERN DEF AR15 9MM 4" BBLUpgrade your AR 15 pistol platform with the Stern Defense 4" 9mm Barrel. This precision engineered barrel is designed to deliver exceptional accuracy and performance in an ultra compact package. Crafted from 4150 chrome moly steel with a durable melonite coating, it offers excellent corrosion resistance and longevity. The 1: 10 twist rate provides optimal stabilization for 9mm projectiles, ensuring consistent accuracy. The barrel's compact size makes