Faxon ARAK-21 Complete Upper | 5.56 NATO | 12.5 in | URSSB556P

The Faxon ARAK-21 is a gas piston-actuated complete upper receiver assembly designed to interface with standard AR-15 lowers using the takedown and pivot pins. It ships as a ready-to-install unit and includes barrel assembly components and a bolt carrier assembly to minimize parts sourcing. Its configuration suits carbine competition use and precision AR-platform shooting where a robust piston system and adjustable gas flow are desired.

Product Specifications

• The manufacturer is Faxon Firearms.
• The model identification is ARAK-21 Complete Upper (URSSB556P).
• The caliber is .223 Rem/5.56 NATO.
• The barrel measures 12.5 inches.
• The rate of twist is 1:8″.
• The barrel material is steel.
• The barrel finish is nitride.
• The upper receiver material is billet aluminum.
• The operation type is gas piston actuated.
• The rail configuration is M4-style quad rails.
• The controls include ambidextrous safety and ambidextrous charging handle.
• The gas system is adjustable.
• The muzzle device is listed as MUZZLOK.
• The listed weight is 5.1 lbs.
• The UPC is 816341025608.

Engineered for shooters who prefer a piston-driven AR upper that installs on a standard lower, the ARAK-21 combines a durable gas system, modular full-length rails, and user-adjustable gas settings to support varied ammunition and suppressor use. Its included BAU components and serviceable bolt carrier assembly make it a practical choice for builders seeking a purpose-built piston upper for competition or precision carbine builds.