Barnes Bullets TSX 458 Caliber .458 300 GR TSX Flat Base 20 Box. Offering four razor sharp petals with deep cutting capability and an impressive ability to retain 100 percent of their original weight they deliver the kind of stopping power that's needed for one-shot kills on big game. These bullets are built to withstand the toughest resistance to twist. Their copper-cores provide reliable ignition and they expand instantly on impact with enough energy to penetrate deeply. Barnes' patented TSX (Triple Shock X) design is one of the most accurate and effective ever created. These live bullets are ready to take down big game. Specifications for Barnes Bullets 30615 TSX 458 Caliber .458 300 GR TSX Flat Base 20 Box: Manufacturer: Barnes Bullet Type: Hollow Point (HP) Flat Base Hollow Point (FBHP) Bullet Weight: 300 grain Projectile Caliber: .458 Caliber Sectional Density: 0.204 Bullet Quantity: 20 Bullet Country of Origin: USA Housing/Frame Material: Copper Fabric/Material: Copper Package Contents: Barnes Bullets 30615 TSX 458 Caliber .458 300 GR TSX Flat Base 20 Box Barnes Bullets 30615 TSX 458 Caliber .458 300 GR TSX Flat Base 20 Box