Action: Semi Auto – Caliber: 5.56 – Barrel Length: 20 – Weight: 7 lb – Through an ingenious and simple arrangement we have solved the main disadvantage of Bullpup rifles; case ejection. Traditional side ejection is not ambidextrous and forward eject like in the FN 2000 or the Kel-Tec RFB is quite complex. – The RDB (Rifle Downward-eject Bullpup) features a rotary bolt with a spring loaded ejector and an extractor facing down. The spent case is pulled backwards along the top of the magazine and then ejected through a vertical chute. The hammer is U-shaped and runs outside the chute and above the magazine. Obviously the bolt travel is longer than traditional designs but well within the ergonomic constraints of a rifle. Other advantages are gravity assisted ejection higher bolt energy at feeding and a slower full auto rate (when applicable). – The RDB is built around a common steel skeleton formed by the receiver and barrel sub-assemblies. Bolt bolt carrier firing mechanism ejector chute and bolt stop are identical for all variations. The short stroke gas operated piston is fully adjustable for different ammunitions and muzzle attachments.