Dark Mountain Arms SA121: This large format bolt-action pistol by Dark Mtn Arms is designed to be the most versatile single-shot pistol available. The barrel is removable to reduce length and pack away or convert to another caliber. - Technical Specifications - Caliber: 9 x 19mm - Action: Bolt-Action - Length (barrel detached): 7.1 inches - Firing Length (barrel attached): 11.5 inches - Height: 6.88 inches - Thickness: