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Upgrade your AR-15 with the Brownells 20" A1 Rifle Barrel. Perfect for Retro builds! 🔥 Lightweight, chrome-lined, and durable.

BROWNELLS AR-15 20" A1 RIFLE BARREL 1-12 ASSEMBLY - BROWNELLS AR-15 20" A1 RIFLE BARREL 1-12 TWIST ASSEMBLY

050806029460 100020999

Restrictions

Is a 'Call to order' product.

Top takeaways

The Brownells Retro A1 20" rifle barrel is designed to replicate the original M16A1 "skinny" barrel, ideal for Retro Rifle™ builds or any lightweight AR-15 setup.
Chambered in 5.56x45, it features a 1-12" twist, chrome-lined bore, and matte black phosphate finish, with a ½"-28 tpi muzzle thread and pre-installed standard rifle barrel extension.
Constructed from 4150 chrome-moly steel, the barrel is magnetic particle inspected to ensure quality and durability, and requires a separate rifle-length gas tube.

Attributes

Cartridge: 5.56 mm NATO
Finish: Black
Gas System Length: Rifle
Length: 20''
Make: AR-15
Muzzle Threads: 1/2-28
Twist: 1-12
Delivery weight: 1.043kg
Shipping height: 25mm
Shipping width: 152mm
Shipping length: 523mm
UPC : 050806029460

Item details

Made in USA
US export classification: 0A501.c

Specifications:
Cartridge: 5.56 mm NATO
Finish: Black
Gas System Length: Rifle
Length: 20''
Make: AR-15
Muzzle Threads: 1/2-28
Twist: 1-12

374.9 374.9 1 GBP

374.9 GBP 34 £374.90

Prices inclusive of duty & VAT.

Product no.: 100020999

Mfr. No.: BABR5512999M

050806029460 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.

In stock - Is a 'Call to order' product.

Delivery time approx. 7-14 days.
More than 10 pieces in USA warehouse

Is a 'Call to order' product.

Delivery time approx. 7-14 days.
More than 10 pieces in USA warehouse

Wish List Ask question

Requires order by phone

Specifications:
Cartridge: 5.56 mm NATO
Finish: Black
Gas System Length: Rifle
Length: 20''
Make: AR-15
Muzzle Threads: 1/2-28
Twist: 1-12

Description:

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.

Restrictions

Is a 'Call to order' product.

Top takeaways

The Brownells Retro A1 20" rifle barrel is designed to replicate the original M16A1 "skinny" barrel, ideal for Retro Rifle™ builds or any lightweight AR-15 setup.
Chambered in 5.56x45, it features a 1-12" twist, chrome-lined bore, and matte black phosphate finish, with a ½"-28 tpi muzzle thread and pre-installed standard rifle barrel extension.
Constructed from 4150 chrome-moly steel, the barrel is magnetic particle inspected to ensure quality and durability, and requires a separate rifle-length gas tube.

Attributes

Cartridge: 5.56 mm NATO
Finish: Black
Gas System Length: Rifle
Length: 20''
Make: AR-15
Muzzle Threads: 1/2-28
Twist: 1-12
Delivery weight: 1.043kg
Shipping height: 25mm
Shipping width: 152mm
Shipping length: 523mm
UPC : 050806029460

Item details

Made in USA
US export classification: 0A501.c

Customers reviews

Customer ratings (4)

4 / 5

Definitely recommended

Excellent 11/10/2018

My experience with this barrel (Brownells No. 100-020-999MB) is excellent. I received mine with an A1 round sight post installed. I paired it with a Colt BCG (No. 160-000-390) with original, surplus handguards, lock washer and 3-prong flash hider. Everything fit well. The barrel nut fits a government wrench and Magpul wrench with no issues. The finish, after 500 rounds, isn't "shiny" anymore - it looks more like a Colt parkerized barrel. My best 100-yard, 5-shot group is 1.56 inches using Hornady Frontier 223 55-grain FMJ. As for the bayonet fit, mine sits 1/16-inch farther back than I think it should but it will work. My M3 bipod fits perfect.

Slightly recommend

After long wait, disappointed. 14/06/2018

Been waiting a year for these to be in stock. It is not true to spec, and required much more fitting than any USGI barrel ever did.

No rollmarks, just the cheesy laser etching UNDER the handguard, where it can not be seen, not even the twist rate or caliber.

Barrel nut was out of spec to the point a barrel nut wrench would not fit. I double checked against several USGI, Colt, Bushmaster, and even PSA. All those were correct, the Brownell's is not.

The spacing from the bayonet mount to the muzzle threading is out of spec, it is about 3/32" too short.

Black shiny, slick finish is not correct. Does not appear to be Manganese phosphate. Machining on the barrel is nothing like the originals when compared side by side.

A2 sight pin? Really?

I am afraid to shoot the thing if this is what they call " an aftermarket barrel made to spec", as it would have failed inspection by gov't purchasing personnel.

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