Official video from Umarex recommending their Walther PPQ Gas Blowback Pistol for training... "This GBB airsoft pistol is a great training aid as well as a lot of fun. The Walther PPQ green gas airsoft pistol from Elite Force and Umarex fits in your existing holster for your centerfire version and allows you to practice drills for a fraction of the cost of shooting centerfire ammunition. The size and weight are close to the 9mm pistol and with the blowback action slide, you get added realistic feedback. The metal magazine that holds the gas and BBs adds to the weight and realistic feel. No matter if you are training for the next match or just out to have some target shooting fun this 6mm airsoft pistol is up for the task."