The Colt Diamondback is a usa-made double-action revolver chambered in .38 Special, introduced in 1966. Primary use: Range/Target, Small Game. Type: Revolver Action: Double-Action Caliber: .38 Special Capacity: 6 Year introduced: 1966, USA Weight: 21 oz Overall length: 6.5" Status: Discontinued Intended use: Range/Target, Small Game