Kel-Tec RDB


The Kel-Tec RDB is a bullpup carbine offered in 5.56×45mm NATO semi-automatic rifle, manufactured by Kel-Tec Industries of Florida. It uses a rotary bolt with a spring loaded ejector and an extractor facing down, ejecting spent shell casings downward, allowing easy ambidextrous use.

Design Details

The RDB was designed to be modular, and is broken down into four Assembly Groups, held together with HK style push-pins:
The RDB operates using the short-stroke piston system, firing from a closed bolt. A gas regulator is built into the Barrel Assembly Group to allow the operator to adjust the amount of gas used to cycle the action. The RDB uses a unique downward ejection method to permit the operator to fire the rifle from either side. During the extraction and ejection cycle, spent casings are dragged rearward over the magazine to the ejection chute located directly behind. The RDB bolt uses dual ejectors to assist in positive ejection, and has been demonstrated to operate normally even if the rifle is turned upside-down. While other bullpup rifles have used forward-ejection to allow ambidextrous use, these solutions tend to add parts and complexity to the design. Other bullpups can be converted to eject from one side to the other but may not be able to do so without special parts.

Variants

The Kel-Tec M43 is a similar design replacing polymer parts with parkerized steel or with wood for the stock furniture. The M43 is fitted with integral folding sights, and accepts standard AR-15 magazines. It features an ambidextrous bolt release, a manually locked back charging handle, and a heat shield over the short stroke piston.