AR57

The makers of the AR-57 set out to create an alternative means to utilize the PS90 magazine and 5.7x28mm round it employed. Sticking with the AR-15 rifle pattern, the upper mounts to a standard AR-15 lower. The AR Five Seven (also known as AR57) is a upper receiver that utilizes a FN PS90 50 round magazine that sits on top of the receiver. The empty casings are ejected downward through the magazine well of the firearm. The magazine mounts horizontally on top of the front handguard. The upper receiver utilizes a straight blowback operation rather than the standard DI gas system employed by the AR-15 rifle.