Hornady Sub-X Features The Flex Tip insert seats inside the bullet s hollow point cavity and combined with long jacket grooves and a flat profile is engineered to trigger reliable expansion even at the reduced velocities subsonic loads produce solving the common problem of hollow points that fail to open below the speed of sound. The lead core supplies the mass needed to maintain penetration depth at those lower velocities while the gilding metal jacket keeps expansion controlled rather than allowing premature fragmentation. Cannelures cut into the jacket give a positive crimp surface which matters most for feeding reliability in semiautomatic pistols and carbines. Handloaders building suppressed .45-caliber ammunition benefit from a bullet designed specifically around subsonic velocities rather than a standard supersonic projectile simply loaded down. At 395 grains this is a heavy-for-caliber option that carries substantial momentum and penetration depth even with reduced velocity which matters for reliable terminal performance on target. This bullet gives reloaders building quiet suppressed .45-caliber loads a purpose-built option rather than a compromise. Hornady Sub-X Specifications Brand: Hornady Model: Sub-X Caliber: 45 Cal Bullet Diameter: .452 Bullet Weight: 395 gr Bullet Material: Jacketed Lead Jacket Material: Brass Count: 50 Available At: GrabAGun