Hornady Sub-X Features The patented Flex Tip insert sits inside the bullet s hollow point cavity and works with long jacket grooves and a flat bullet profile to trigger reliable expansion even at the reduced velocities that come with subsonic loads solving the classic problem of hollow points failing to open up when they re moving too slowly. The lead core provides the mass needed for deep penetration at these lower velocities while the gilding metal jacket controls expansion so the bullet doesn t fragment prematurely. Cannelures machined into the jacket give a positive crimp surface for the case which matters most in semiautomatic pistols and carbines that need consistent cartridge overall length to feed reliably. Because subsonic ammunition is frequently paired with a suppressor this bullet s expansion characteristics were specifically engineered around the lower impact velocities that suppressed subsonic shooting produces. Handloaders working up loads for suppressed .45-caliber platforms get a bullet designed from the ground up for that use case rather than a standard supersonic projectile pushed to lower velocity. At 410 grains this is a heavy-for-caliber option intended to carry momentum and penetration depth that a lighter subsonic bullet can t match. Hornady Sub-X Specifications Brand: Hornady Model: Sub-X Caliber: 45 Cal Bullet Diameter: .458 Bullet Weight: 410 gr Core Material: Lead Ballistic Coefficient: .285 Sectional Density: .279 Jacket Material: Brass Count: 50 Available At: GrabAGun