The PWS Diablo is an AR-pistol with a 7.75-inch barrel using PWS's proprietary long-stroke piston operating system. The piston reduces gas exposure to the shooter and keeps the action cooler than direct impingement in a compact pistol format. Type: Pistol Action: Long Stroke Piston Caliber: 5.56x45mm Capacity: 30 Year introduced: 2018, USA Weight: 6.5 oz Overall length: 22" Status: Active Intended use: Home Defense, Range, Duty