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Rifle Parts Barrel Parts Rifle Barrels BROWNELLS BRN AR-15/A1 CARBINE 5.56MM 11.5" 1-12 TWIST BARREL ASSEMBLY Support

The Brownells A1 Carbine Barrel Assembly features a durable 4150 chrome-moly steel construction, 5.56 NATO chamber, and includes essential components for retro builds.

BROWNELLS BRN AR-15/A1 CARBINE 5.56MM 11.5" 1-12 TWIST BARREL ASSEMBLY

050806003712 078000377

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The Brownells A1 Carbine Barrel Assembly features a durable 4150 chrome-moly steel construction, 5.56 NATO chamber, and includes essential components for retro builds.
AR-15 M16A1 RETRO BARREL ASSEMBLIES - BRN AR-15/A1 CARBINE 5.56MM 11.5" 1-12 TWIST BARREL ASSEMBLY
274.9 GBP 12 £274.90 *
In stock
Cartridge: 5.56 mm NATO Contour: Carbine Finish: Black Length: 11.5'' Make: AR-15 Muzzle Threads: 1/2-28 Twist: 1-12 Product no.: 078000377
In stock
274.9 GBP 12 £274.90 *
The Brownells Retro A1 Barrel Assembly features a chrome-lined 5.56 NATO chamber, durable 4150 steel construction, and includes essential components for authentic builds.
AR-15 M16A1 RETRO BARREL ASSEMBLIES - BRN AR-15/M16A1 RETRO CARBINE 5.56MM 11.5" 1-7 BBL ASSEMBLY
274.9 GBP 0 £274.90 *
Backorderable
Cartridge: 5.56 mm NATO Finish: Black Gas System Length: Carbine Length: 11.5'' Make: AR-15 Muzzle Threads: 1/2-28 Twist: 1-7 Product no.: 078000461
Backorderable
274.9 GBP 0 £274.90 *
274.9 274.9 2 GBP
274.9 GBP £274.90

Prices inclusive of duty & VAT.

Product no.: 078000377

Mfr. No.: BABR5512377M

050806003712 078000460 At 10.3" this is the shortest version of our A1 profile AR-15 barrel assembly. Matching the exterior contours of commonly used carbine barrels of the 1960s through the 2000s, it’s ready to lend an extra touch of authenticity to your next build. Or install one for extra weight savings on a lightweight AR-15 SBR, PDW, or pistol - following all NFA rules, of course! Like all our Brownells Retro A1 barrels, the 10.3" model is machined from hardened 4150 steel, then MPI inspected to detect hidden flaws (so we can pull it from the supply chain BEFORE it leaves the factory) and given a hard black phosphate finish. It’s chambered for the modern 5.56 NATO cartridge, with speedy 1-7" rifling in the nitride bore, so the 10.3" A1 Retro barrel plays nicely with current-production ammo. Ordnance-grade 4150 chrome-moly carbon steel Durable QPQ finish 5.56 NATO chambered with 1-7" twist rifling Uses CARBINE LENGTH gas tube .070" gas port All NFA rules apply Up front, the 10.3" Retro A1 barrel has ½-28" tpi muzzle threads, ready to accept a "retro" flash suppressor or modern muzzle device / sound suppressor, and on the other end a standard carbine barrel extension’s already installed. Also installed: a 625" gas block/front sight base (F marked) with bayonet lug, sight post, detent, spring, sling swivel, Delta ring, barrel nut, weld spring, snap ring, and round handguard cap. 078000461 & 078000377 The AR-15 is more than a half-century old, and the rifle and subsequent platforms have undergone a great deal of evolution. Now, aficionados of the system can build reproduction of early rifles with the Brownells A1 Carbine Barrel Assembly. The Brownells A1 Carbine Barrel Assembly is designed to be the ideal component of any XM177 rifle reproduction or any lightweight AR build, coming equipped with most of the materials necessary to complete a retro build. Barrel length: 11.5" (You are responsible for NFA compliance!) Twist rate: 1-7" or 1-12" Carbine-length gas system Threaded with 1/2"-28 TPI threads Chrome lined chamber and bore The Brownells A1 Carbine Barrel Assembly comes equipped with a front-sight base, .625"", no F marks, complete with sight post, detent, spring, sling swivel, rivet, flat Delta ring, barrel nut, weld spring, snap ring, and round handguard cap installed 078000462 & 100020996 The Brownell’s Retro A1 12.7" carbine length barrel assembly. Chambered in 5.56x45mm NATO, the chrome lined barrel is available with your choice of 1-7" or 1-12" rifling and finished in black phosphate with an overall length of 12.7”. Muzzle threads are ½""-28, and in back there's a standard barrel extension. Each Retro A1 12.7" carbine barrel assembly includes a front-sight base, .625", no F marks, complete with sight post, detent, spring, sling swivel, rivet, flat Delta ring, barrel nut, weld spring, snap ring, and round handguard cap installed. Machined from 4150 chrome moly steel. The barrel you need for your next Retro Rifle build! NOTE: These barrels do not have bayonet lugs. 100020999 The Brownells Retro A1 rifle length barrel replicates exactly the exterior contours of the original "skinny" barrel of the M16A1 rifle, so it's ideal for building your own Retro Rifle™ OR any AR-15 where a lightweight barrel is desirable. Chambered in 5.56x45, this chrome-lined barrel has a 1-12" twist and is finished in matte black phosphate, with an overall length of 20". The muzzle threads are ½"-28 tpi, and in the back a standard rifle barrel extension is pre-installed. 5.56 NATO chamber (also accepts .223 Rem) Original 1-12" rifling compatible with heavier bullets Chrome-lined bore Requires a rifle-length gas tube (available separately) Available as Stripped or complete Barrel Assembly This Brownells Retro A1 rifle barrel is machined from ultra-strong 4150 chrome-moly steel, and is magnetic particle inspected when finished to ensure there are no hidden flaws that could shorten its service life. 100021012 The Brownell’s Retro A1 rifle length barrel assembly. Chambered in 5.56x45, the chrome lined barrel has a 1-7 twist and finished in black phosphate with an overall length of 20”. Muzzle threads are ½-28 and features a standard rifle barrel extension. The assembly includes a front sight base, .625 No F Marks, sight post, detent, spring, sling swivel, rivet, flat delta ring, barrel nut, weld spring, snap ring, and triangular handguard cap. Everything you need for your Retro barrels!
In stock More than 10 pieces in USA warehouse
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Description Specification Customers reviews Accessories

BROWNELLS BRN AR-15/A1 CARBINE 5.56MM 11.5" 1-12 TWIST BARREL ASSEMBLY

274.9 GBP £274.90

Prices inclusive of duty & VAT.

Is a 'Call to order' product.
Requires order by phone

Description:

A Critical Component of Any Retro AR-15 Build

The AR-15 M16A1 Retro Barrel Assemblies from BROWNELLS are designed to enhance the authenticity and performance of your retro AR-15 builds. With multiple options available, including the 11.5" 1-12 twist barrel assembly, you can achieve the classic look and feel of the original models.

Product Features:

  • Barrel Length: 11.5" (NFA compliance required)
  • Twist Rate: 1-7" or 1-12"
  • Carbine-length gas system
  • Threaded with 1/2"-28 TPI threads
  • Chrome lined chamber and bore

At 10.3", this barrel assembly is the shortest version of our A1 profile, matching the contours of carbine barrels from the 1960s to the 2000s. It’s perfect for building a lightweight AR-15 SBR, PDW, or pistol while adhering to NFA regulations.

Machined from hardened 4150 steel and MPI inspected, these barrels are finished with a hard black phosphate coating. The 10.3" model is chambered for the modern 5.56 NATO cartridge, featuring speedy 1-7" rifling in the nitride bore, ensuring compatibility with current-production ammunition.

Additional Components:

The assembly includes:

  • ½-28" tpi muzzle threads for retro flash suppressors
  • Standard carbine barrel extension pre-installed
  • 625" gas block/front sight base (F marked) with bayonet lug
  • Complete with sight post, detent, spring, sling swivel, Delta ring, barrel nut, weld spring, snap ring, and round handguard cap

Whether you're replicating early rifles or building a lightweight AR, the Brownells A1 Carbine Barrel Assembly is the ideal choice for enthusiasts looking to create an authentic experience.

Specifications:

  • Ordnance-grade 4150 chrome-moly carbon steel
  • Durable QPQ finish
  • All NFA rules apply

Upgrade your build with the Brownells Retro A1 Barrel Assemblies and enjoy a piece of history with every shot!



Restrictions

  • Is a 'Call to order' product.

Top takeaways

  1. The Brownells A1 Carbine Barrel Assembly is designed for building XM177 rifle reproductions or lightweight AR builds.
  2. This barrel assembly is 11.5" long with a choice of a 1-7" or 1-12" twist rate and is chrome lined for durability.
  3. It comes with a front-sight base and necessary components pre-installed for ease of assembly.

Attributes

  • Cartridge: 
    5.56 mm NATO
  • Contour: 
    Carbine
  • Finish: 
    Black
  • Gas System Length: -
  • Length: 
    11.5''
  • Muzzle Threads: 
    1/2-28
  • Twist: 
    1-12
  • Weapon type: 
    AR-15
  • Delivery weight: 0.726kg
  • Shipping height: 51mm
  • Shipping width: 102mm
  • Shipping length: 305mm
  • UPC: 050806003712

Item details

Made in USA
US export classification: 0A501.c

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Variations:

The Brownells A1 Carbine Barrel Assembly features a durable 4150 chrome-moly steel construction, 5.56 NATO chamber, and includes essential components for retro builds.
AR-15 M16A1 RETRO BARREL ASSEMBLIES - BRN AR-15/A1 CARBINE 5.56MM 11.5" 1-12 TWIST BARREL ASSEMBLY
274.9 GBP 12 £274.90 *
In stock
Cartridge: 5.56 mm NATO Contour: Carbine Finish: Black Length: 11.5'' Make: AR-15 Muzzle Threads: 1/2-28 Twist: 1-12 Product no.: 078000377
In stock
274.9 GBP 12 £274.90 *
The Brownells Retro A1 Barrel Assembly features a chrome-lined 5.56 NATO chamber, durable 4150 steel construction, and includes essential components for authentic builds.
AR-15 M16A1 RETRO BARREL ASSEMBLIES - BRN AR-15/M16A1 RETRO CARBINE 5.56MM 11.5" 1-7 BBL ASSEMBLY
274.9 GBP 0 £274.90 *
Backorderable
Cartridge: 5.56 mm NATO Finish: Black Gas System Length: Carbine Length: 11.5'' Make: AR-15 Muzzle Threads: 1/2-28 Twist: 1-7 Product no.: 078000461
Backorderable
274.9 GBP 0 £274.90 *

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