The Blackhawk Convertible includes two cylinders: one chambered for .357 Magnum and one for 9mm, requiring moon clips. The shooter can switch between cartridges by swapping cylinders without tools. The 9mm cylinder allows economical practice with inexpensive 9mm ammunition while the .357 cylinder provides full hunting or defensive capability. Type: Revolver Action: Single-Action Caliber: .357 Magnum / 9mm Capacity: 6 Year introduced: 1999, USA Weight: 42 oz Overall length: 10.5" Status: Active Intended use: Recreational, Hunting, Cowboy Action, Field, Self-Defense