X-Treme Bullets Rifle Bullets .308 Caliber 147 Grain Full Metal Jacket 500 Bullets. We use state of the art manufacturing technology deigned to encompass the lead core in a copper jacket which is not intended to expand upon impact with the target. A cannelure is added to provide a better hold during the crimp process. These bullets are ideal for target shooting plinking and varmint hunting. Specifications for X-Treme Bullets Rifle Bullets .308 Caliber 147 Grain Full Metal Jacket: Manufacturer: X-Treme Bullets Gun Type: Pistol Bullet Type: Full Metal Jacket (FMJ) Caliber: .308 Winchester Cartridge Type: Brass Bullet Weight: 147 grain Projectile Caliber: .308 Caliber Diameter: 0.308 in Core Material: Lead Jacket Material: Copper Bullet Quantity: 500 Bullet Package Contents: X-Treme Bullets .308 Winchester 147 Grain Full Metal Jacket Pistol Ammunition X-Treme Bullets XB308FMJ147B500: Rifle Bullets .308 Caliber 147 Grain Full Metal Jacket