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Questions & Answers
In the specifications, it says 9 mm but the description says 5.56 is this just a typo in the specs ? Manufacturer Answer

Yes, this is a typo. The barrel unit is chambered for 5.56 NATO ammunition.

by Faxon Firearms, Manufacturer, February 19, 2026
4 Models Available
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Product Info for Faxon Firearms Arak-21 5.56 Nato Rifle Threaded Rifle Barrel

Easily swap from 7.62x39 to 5.56 NATO in a matter of minutes with this caliber conversion kit for the ARAK-21. The kit includes a Barrel Assembly Unit (BAU), bolt, firing pin, and firing pin return spring. By swapping out the barrel and bolt, you will be able to swap calibers on your ARAK-21. Built for modularity and durability, the ARAK-21 affords the end user to configure the weapon system to fit their needs.image

WARNING: California`s Proposition 65

Specifications for Faxon Firearms Arak-21 5.56 Nato Rifle Threaded Rifle Barrel:

Manufacturer: Faxon Firearms
Color: Black
Caliber: 9mm Luger
Barrel Profile: Medium
Barrel Twist Rate: 1-8
Barrel Material: 416R Stainless Steel
Flutes: No
Gun Make: AR Platform
Gun Model: Faxon ARAK-21
Condition: New

Features of Faxon Firearms Arak-21 5.56 Nato Rifle Threaded Rifle Barrel:

  • Purpose-built for ARAK-21 5.56 NATO platforms
  • 12.5in barrel length for compact handling and maneuverability
  • Not a caliber conversion – remains 5.56 NATO
  • Ships fully assembled:
  • Barrel
  • Trunnion
  • Adjustable gas system

Package Contents:

  • Faxon Firearms Arak-21 5.56 Nato Rifle Threaded Rifle Barrel

Faxon Firearms Arak-21 5.56 Nato Rifle Threaded Rifle Barrel Orderable Models

List of Orderable Models

  • Faxon Firearms Arak-21 5.56 Nato Rifle Non-Threaded Rifle Barrel, 12.5in, Custom, 1-8 Twist, Conversion Kit, Black, ARAK21BAUCONVKIT-104S-12 , MPN: ARAK21BAUCONVKIT-104S-12 , UPC: 816341029231 , Code: 11I-RTB-NBHG7Y-ARAK21BAUCONVKIT-104S-12
  • Faxon Firearms Arak-21 5.56 Nato Rifle Non-Threaded Rifle Barrel, 12.5in, Custom, 1-8 Twist, Assembly Unit, Black, ARAK21BAUONLY-104S-12 , MPN: ARAK21BAUONLY-104S-12 , UPC: 816341029194 , Code: 11I-RTB-NBHG7Y-ARAK21BAUONLY-104S-12
  • Faxon Firearms Arak-21 5.56 Nato Rifle Non-Threaded Rifle Barrel, 16in, Custom, 1-8 Twist, Assebly Unit, Black, ARAK21BAUONLY-104-16 , MPN: ARAK21BAUONLY-104-16 , UPC: 816341029200 , Code: 11I-RTB-NBHG7Y-ARAK21BAUONLY-104-16
  • Faxon Firearms Arak-21 5.56 Nato Rifle Non-Threaded Rifle Barrel, 16in, Custom, 1-8 Twist, Conversion Kit, Black, ARAK21BAUCONVKIT-104-16 , MPN: ARAK21BAUCONVKIT-104-16 , UPC: 816341029248 , Code: 11I-RTB-NBHG7Y-ARAK21BAUCONVKIT-104-16
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