Kel‑Tec RDB 5.56 NATO 17.3in Bullpup, 20rd

The Kel‑Tec RDB is a compact, ambidextrous bullpup rifle chambered for 5.56 NATO / .223 Remington with a threaded 17.3-inch steel barrel. Its downward-ejection system and configurable gas piston make it suitable for shooters seeking a short overall length platform while retaining AR-15 magazine compatibility.

Designed with a synthetic OD green bullpup stock and a Mil-Spec Picatinny rail, this RDB variant emphasizes compact handling, modular accessories, and true ambidextrous operation without sacrificing the ballistic advantages of a mid-length barrel.

Key Specifications

• The caliber is 5.56 NATO / .223 Rem.
• The action type is Semi-Automatic.
• The barrel measures 17.3 inches and is described as a steel, threaded barrel.
• The magazine capacity is 20 rounds (accepts standard AR-15 magazines).
• The overall length is 27.3 inches.
• The unloaded weight is listed as 6.7 pounds.
• The twist rate is 1:7.
• The stock is OD green synthetic in a bullpup configuration.
• The barrel finish is black nitride and the metal finish is described as blued/black.
• Notable features include downward ejection and an adjustable gas piston system.

The RDB combines a short overall package with features intended for practical, adaptable use: ambidextrous controls, downward ejection to accommodate left- and right-handed shooters, a smooth trigger system, and an adjustable gas piston that supports a range of loads and suppressor use. Its 17.3-inch barrel and AR-15 magazine compatibility make it a practical option where compact handling and familiar magazine interfaces are priorities.