What's in the Box Charter Arms Pitbull 45 ACP Stainless Double-Action Revolver Owner's Manual Introducing the Charter Arms .45 ACP caliber Pitbull. The unique design provides a dual coil spring assembly located in the extractor which allows for the insertion and retention of the .45 ACP caliber cartridge in each chamber of the revolvers cylinder. (No moon clips required) This patented system allows the shooter ease of ejecting spent cartridges for immediate reloading. Charter Arms has taken the difficulty of rimless loading and ejection to the simplicity of the rimmed cartridge in the revolver industry. Firearm Specifications Model: 74520 Finish: Stainless Steel Frame: Matte Grip: Full Barrel length: 2.5" Capacity: 5-shot Caliber: .45 ACP Hammer: Standard Weight: 22 oz.