MOSSBERG 590 Pistol Grip - Specs Caliber: 12 Gauge Action: Pump-action Barrel Length: Typically 20" on the standard 590 field/security configuration Magazine Capacity: 8+1 rounds with 2 3/4" shells on common 8-shot configurations Overall Length: Approximately 40" Chamber: 3" Stock: Pistol-grip configuration Receiver: Aluminum Safety: Ambidextrous top tang safety Sights: Bead sight on many standard models Finish: Matte/blued or parkerized, depending on model Gun-shop listing: Mossberg 590 12 Gauge Pump-Action Shotgun, Pistol Grip, 20" Barrel, 8-Round Capacity, 3" Chamber.