Hornady Sub-X .338 Caliber Rifle Bullets 307 Grain Subsonic Expanding 50 Bullets. Designed to provide deep penetration below the speed of sound Sub-X features a lead core. Long grooves in its gilding metal jacket combine with its flat profile and the patented Flex Tip insert within the bullets hollowpoint cavity to help it expand reliably at low velocities. Cannelures provide positive case crimp making Sub-X ideal for semiautomatic firearms. Specifications for Hornady Sub-X .338 Caliber Rifle Bullets 307 Grain Subsonic Expanding: Manufacturer: Hornady Bullet Type: Subsonic eXpanding (Sub-X) Hollow Point (HP) Bullet Weight: 175 grain Projectile Caliber: .308 Caliber .338 Caliber Bullet Quantity: 50 Bullet Dimensions: 2.15 X 3.50 X 4.10 in Number of Rounds: 100 Features of Hornady Sub-X .338 Caliber Rifle Bullets 307 Grain Subsonic Expanding EXPANDS AT SUBSONIC VELOCITIES: Patented Flex Tip technology aids in expansion at velocities as low as 900 fps. PROVEN PERFORMANCE: Meets FBI protocol for terminal ballistic test requirements. POSITIVE CASE CRIMP: Lead core bullet with cannelured jacket provides positive case crimp for use in semiautomatics. WIDE RANGE OF GUNS: Designed to fit feed and function in a variety of firearms including gas system guns. Package Contents: Hornady Sub-X .338 Caliber Rifle Bullets 307 Grain Subsonic Expanding Hornady 33394: Sub-X .338 Caliber Rifle Bullets 307 Grain Subsonic Expanding 50 Bullets