The Faxon ARAK-21 Complete Upper (brand part number URSSB556SSMB) brings Faxon’s ARAK-21 short-stroke gas piston platform to a 5.56 NATO chambering with a 16-inch barrel. Unlike a standard direct-impingement AR-15 upper, the ARAK-21 system runs a short-stroke piston operating system that keeps combustion gases and carbon out of the receiver, for a cleaner-running, cooler-cycling upper. This complete upper ships with a muzzle brake installed to help manage recoil and muzzle rise in semi-automatic fire. At 16 inches, the barrel clears the federal rifle barrel-length minimum, and this is an upper receiver group only, sold without a lower receiver, so the buyer completes the rifle with a compatible AR-15 lower.

Key Specifications

• Chambered in 5.56x45mm NATO/.223 Remington.
• Barrel length is 16 inches, clearing the federal rifle barrel-length minimum.
• Runs Faxon’s ARAK-21 short-stroke gas piston operating system.
• Action is semi-automatic.
• Ships with a muzzle brake installed.
• Sold as an upper receiver group only, without a lower receiver.

Frequently Asked Questions

Does this include a lower receiver? No, this is a complete upper receiver group only; the buyer supplies a compatible AR-15 lower to finish the rifle.

What operating system does the ARAK-21 use? A short-stroke gas piston system, which keeps combustion gases out of the receiver for cleaner cycling than direct impingement.

Does this upper include a muzzle device? Yes, it ships with a muzzle brake installed.

Buy the Faxon ARAK-21 Complete Upper

Order the Faxon ARAK-21 upper from our Lubbock, Texas gun shop for fast, insured shipping. Browse more Faxon Firearms AR rifle parts and uppers for your build.