Faxon Firearms Duty Series Barrel - 12.5" - 5.56 NATO - Gunner Profile - Mid-Length
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- Free standard shipping on orders $139+ details
- 90-day no-hassle returns policy
- Backed by the Faxon Firearms Warranty! what it covers
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Product description
Faxon Duty Series 12.5″ 5.56 NATO Barrel – Gunner Profile – Mid-Length Gas
Features
- 12.5″ barrel chambered in 5.56 NATO
- Gunner profile for balanced weight and durability
- Mid-length gas system
- 1:8 twist rate
- 4150 CMV steel construction
- Button rifled with M4 barrel extension
- 11-degree target crown
- Salt bath nitride finish inside and out
The Faxon Duty Series 12.5″ barrel features the proprietary Gunner profile, combining the strength of a government contour near the chamber with the weight savings of a pencil profile forward of the gas block. This design shifts balance rearward for improved handling and reduced fatigue without sacrificing durability. Manufactured in-house from 4150 CMV steel, each barrel is stress relieved, air-gauge tested, headspaced, and finished in a full salt bath nitride treatment for long-term performance.
Specifications
- Brand: Faxon Firearms
- Series: Duty Series
- MPN: 15A58M125NGQ
- Caliber: 5.56 NATO
- Barrel Length: 12.5″
- Twist Rate: 1:8
- Gas System: Mid-length
- Profile: Gunner
- Material: 4150 CMV steel
- Rifling: Button rifled
- Barrel Extension: M4
- Muzzle Thread: 1/2×28
- Crown: 11-degree target crown
- Finish: Salt bath nitride (inside and outside)
- Compatibility: AR-15 pattern rifles
What’s Included
- 1x Faxon Duty Series 12.5″ 5.56 NATO Barrel
Customer reviews
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Questions & Answers 2
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Faxon's website says this takes a .625" gas block, but in the answer to the previous question AT3 says it takes a .750 gas block. It would be nice if they clarified it and put the correct gas journal spec in the description.
KevB · Jul 3, 2026AT3 Support Team — Faxon's official specifications state this 12.5" Gunner profile barrel uses a .625" gas block journal, and we apologize for any previous conflicting information.
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What size gas block fits this barrel?
Chris · Jun 5, 2026AT3 Support Team — The Faxon Firearms 12.5" Gunner Profile barrel requires a standard .750" low-profile gas block.
Warranty & returns
Backed by the Faxon Firearms Warranty!
Faxon Firearms Warranty
We do understand that life happens and that often a purchase will need to be returned. Customers may return any product, for any reason, in line with the requirements & policies below.
For any errors on Faxon’s part, after notification from the customer, Faxon will dispatch a Fed-Ex Ground label for the return of the product. Upon receipt and inspection at Faxon, a replacement will be sent to the customer via Fed-Ex Ground with tracking information sent to the customer.
REQUIREMENTS
- Faxon will only refund products purchased directly through Faxon Firearms.
- If you purchased a product through one of Faxon’s authorized dealers and would like to return the product for a refund, you must contact the dealer for your refund.
- Merchandise must be in new condition with original packaging
- Merchandise must be return-shipped in a protective box
- A full refund including shipping if the return resulted from our error, otherwise we will deduct the shipping costs from the refund.
- All product replacements done under warranty can be handled by Faxon directly.
- The customer will receive a refund within 10 business days of our receiving your return. The refund issued in the same form of payment used for purchase.
- No return will be granted for a product that is modified in any way
- No returns for refund after 30 days from the delivery date of the product.
- There will be a 15% restocking fee on all returns.
Disclaimer: Manufacturer’s warranty is subject to change without prior notice.
90-day no-hassle returns
The AT3 Tactical store has a 90 day no-hassle return policy for products in good condition. You can view the full details of our return policy here.
If you encounter an issue or defect with a product after 90 days of your purchase, you can refer to the manufacturer for a warranty claim. Their policies are below.
