Not exactly an airsoft rifle, but it's interesting to learn more about training rifles, such as this Umarex T4E TM4 CO2-powered Training Rifle that is available at AirRattle... "The T4E TM4 is a new MilSim training weapon brought to you by Umarex. The T4E operates off of C02 cartridges that are put into the magazine, and you are capable of getting 30-40 rounds out of one capsule. Each magazine is capable of holding 14 rounds, but it's recommended to use 13 rounds to prevent the powder balls or paint balls from rupturing. The realistic feel and weight of the gun really help simulate military simulation training and law enforcement training."