Faxon Firearms Duty Series AR-15 Barrel - 16" - .400 Legend - Gunner Big Bore Profile - Carbine-Length - 1:16 Twist
or 4 interest-free payments of $43.00 with 
6 Magazines Per Order: Due to extreme volume, we are limiting sales of magazines to 6 per customer order. This applies to individual and bundled magazines. AT3 reserves the right to cancel any order over the 6 magazine limit.
- Free standard shipping on orders $139+ details
- 90-day no-hassle returns policy
- Backed by the Faxon Firearms Warranty! what it covers
Product description
Straight-Wall .400 Legend Power for a 16″ AR-15 Build
Features
- 16″ .400 Legend (SAAMI) barrel for compatible AR-15 upper receiver builds
- Gunner Big Bore contour reduces forward weight for better balance
- Button-rifled 4150 CMV steel with six-groove, 1:16 right-hand twist
- QPQ nitride inside and outside for surface hardness and corrosion resistance
- Carbine-length gas system with .875″ gas block journal
- 11/16×24 muzzle threads and target crown
- Duty Series stress relief, air gauging, magnetic-particle inspection, and headspace checks
- Made in the USA
The Faxon Firearms Duty Series .400 Legend barrel is button-rifled from 4150 CMV steel and finished with QPQ nitride inside and out. Its Gunner Big Bore contour keeps more material behind the gas block and tapers toward the muzzle to cut forward weight, while the 16″ length, carbine-length gas system, and 1:16 twist make it a practical hunting and general-purpose configuration without a short-barreled rifle setup. Each barrel ships with a Big Bore M4 extension installed, pinned, and headspaced.
Note: Requires a 6.8 SPC / .224 Valkyrie bolt face and .400 Legend magazines. Gas block, gas tube, muzzle device, and bolt carrier group are sold separately. Large window upper is recommended.
Specifications
- Brand: Faxon Firearms
- Series: Duty Series
- Platform: AR-15
- Chamber: .400 Legend, SAAMI
- Nominal Length: 16″ (16.13″ actual)
- Profile: Gunner Big Bore
- Material: 4150 CMV steel
- Finish: QPQ nitride, matte black
- Twist Rate: 1:16 right-hand, six-groove, button-rifled
- Gas System: Carbine-length
- Gas Block Diameter: .875″
- Gas Block Journal Length: 1.9″
- Gas Port Diameter: .109″
- Muzzle Threads: 11/16×24 (.625″ thread length)
- Crown: Target
- Barrel Extension: FF-200 BB Big Bore M4, black oxide
- Weight: 2.00 lb (32 oz)
- Warranty: Faxon Lifetime Guarantee
What’s Included
- Faxon Firearms Duty Series 16″ .400 Legend AR-15 Barrel with Big Bore M4 extension installed, pinned, and headspaced
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Questions & Answers
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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.