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Faxon Firearms

Faxon Firearms ARAK-21 16" 5.56 NATO Complete Upper

Long-stroke piston upper with an ambidextrous non-reciprocating forward side charging handle, selectable ejection, and a 5-position adjustable gas regulator.

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Quick Specs

Price
$828
Weight
N/A
Brand
Faxon Firearms
Category
upper

Features

  • 5.56 NATO
  • 16" barrel, 1/2x28 threads
  • Long-stroke gas piston operation
  • Non-reciprocating ambidextrous forward side charging handle
  • Selectable left/right ejection
  • 5-position adjustable gas regulator

Capability Boosts

Reliability+3
Suppression+2
Modularity+2

Recommended For

Duty/Patrol+5
duty+5
Outdoor Defense+5
suppressed shooting+5
suppressed use+5
suppressor host+5

+13 more

Where to Buy

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Optics PlanetBest available

Faxon Firearms ARAK-21 16in 5.56 Complete Upper, URSSB556

$828.00
In stock
1h ago
View offer

Compatibility Tags

family: ar-patternthread: 1/2x28

Overview

The Faxon ARAK-21 is a long-stroke gas piston upper that drops onto any standard AR-15 lower, blending the AR ergonomic shell with an AK-style operating system. Instead of routing gas back into the receiver like a direct-impingement AR, the ARAK-21 runs a long-stroke piston and op-rod carrier that keeps fouling and heat out of the action. The op-rod carrier reciprocates inside the receiver, but the forward-mounted side charging handle stays put while the gun cycles, so there is no rear charging handle slot and the optic rail stays clear front to back.

The charging handle is fully ambidextrous and can be swapped to either side of the upper, and ejection is independently selectable left or right. That combination makes the ARAK-21 one of the few uppers that a left-handed shooter can run without a single right-handed compromise: charge on the left, eject to the left, and never break the firing grip. The 5-position adjustable gas regulator is the other half of the appeal. Three cycling positions let shooters tune the gas for standard or adverse-condition reliability, a dedicated suppressed setting cuts back-pressure and gas-to-face, and a single-shot setting closes the gas entirely for manual operation.

The 16-inch 5.56 NATO barrel is threaded 1/2x28 for standard AR-15 muzzle devices and 5.56-rated suppressors, and the aluminum free-float handguard carries a full-length Picatinny rail up top for optics and backup sights. Because the entire system mounts to a mil-spec lower, the only build decisions left are the lower, a muzzle device or can, and an optic. For shooters who want a tunable, ambidextrous, piston-driven side charger, the ARAK-21 is the most complete drop-in path.

Key Features

  • Long-stroke gas piston operation keeps fouling and heat out of the receiver
  • Forward side charging handle, fully ambidextrous and swappable to either side
  • Selectable left or right ejection for true ambidextrous operation
  • 5-position adjustable gas regulator: three cycling positions plus dedicated suppressed and manual single-shot settings
  • 16" 5.56 NATO barrel threaded 1/2x28 for standard muzzle devices and suppressors
  • Aluminum free-float handguard with a full-length Picatinny top rail
  • Drops onto any standard AR-15 lower receiver

Pros

  • +Fully ambidextrous: swappable charge side plus selectable ejection
  • +Adjustable gas makes it one of the most suppressor-friendly side chargers
  • +Piston operation runs cleaner and cooler than direct impingement
  • +Clear top rail front to back with no rear charging handle slot
  • +Drops onto any standard AR-15 lower

Cons

  • Heavier than a comparable direct-impingement upper
  • Forward charging handle placement takes acclimation versus a rear handle
  • Premium price over a standard DI complete upper
  • Proprietary piston system limits aftermarket parts support

Detailed Specifications

caliber
5.56 NATO
barrelLength
16"
gasSystem
Long-stroke gas piston, 5-position adjustable regulator
operation
Piston-driven, non-reciprocating forward side charging handle
chargingHandle
Ambidextrous forward side charging handle (swappable side)
ejection
Selectable left or right
threadPitch
1/2x28
handguardType
Aluminum free-float, full-length Picatinny top rail
receiverMaterial
Aluminum
lowerCompatibility
Standard AR-15 lower receiver
model
URSSB556

Compatible Platforms

+130 more

Pairs Well With

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