Kel-Tec RDB: The Ambidextrous Bullpup Rifle March 18, 2023 The Kel-Tec RDB is a ground-breaking bullpup carbine that has revolutionized the platform. Manufactured by Kel-Tec Industries of Florida, this semi-automatic rifle is chambered in 5.56×45mm NATO. The RDB is a fully ambidextrous bullpup rifle,