X-Treme Bullets .38 Special 158 Grain Semi Wadcutter Pistol Ammo 500 Rounds. X-Treme Bullets process starts with a lead billet that is extruded into wire. The lead wire is then swaged into a core. The cores are copper plated then restruck once more. Though not common in the industry this restrike process produces a bullet that is more uniform with a more precise diameter and a smoother finish for a better shooting and better looking bullet. Specifications for X-Treme Bullets Pistol Bullets .38 Special 158 Grain Semi Wadcutter: Manufacturer: X-Treme Bullets Gun Type: Pistol Bullet Type: Semi Wadcutter (SWC) Caliber: .38 Special Cartridge Type: Brass Bullet Weight: 158 grain Diameter: 0.357 in Core Material: Lead Jacket Material: Copper Projectile Caliber: .38 Caliber Bullet Quantity: 500 Bullet Package Contents: X-Treme Bullets Pistol Bullets .38 Special 158 Grain Semi Wadcutter X-Treme Bullets XB38SW158B500: .38 Special 158 Grain Semi Wadcutter Pistol Ammo 500 Rounds