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BRN-4 STRIPPED BARRELS CHROME LINED Reviews & Ratings

Brownells BRN-4® HK® 416 compatible barrels, now with chrome bore and chamber.

Historically extremely hard to procure, HK® 416 compatible barrels are now available as part of the BRN-4 lineup. Available in barrel lengths of 10.4, 13.7, 14.5 and 16 inch as well as medium and heavy barrel countours, these barrels are suitable for any need. Machined by Faxon, these barrels fit BRN-4 upper receivers and early generations of HK® 416 upper receivers and components. They are the perfect fit with the BRN-4 bolt carrier group and gas block (search “BRN-4” for all parts).

Chrome lined bore and chamber of these barrels has been the go-to for hard use rifle barrels for decades, and you will be extremely pleased with the smooth and crisp application by Faxon in these bores. The chrome is well applied, and just extends over the crown of the barrel and the edge of the chamber. Barrels are button rifled from 4150 chrome moly steel, the top choice for hard use barrels, with a 1-7 twist and have commonly used ½-28 muzzle threads for the attachment of the muzzle device of your choice. A matte black phosphate provides a corrosion resistant exterior.

The longer barrel extension of the BRN-4 allows for a robust matchup to the upper receiver, and a simple install with the BRN-4 barrel nut (430-100-141). 5.56x45mm NATO chamberings allow for a wide variety of commercially found ammunition to function, as well as 223 Remington cartridges. No need to worry about picking the right gas system length, as all of these barrels have the same piston rod assembly (078-000-644), just be sure to pick the correct BRN-4 gas block to match your overall barrel length, (078-000-708 & 078-000-709). The 13.7 inch barrel should use the 14.5/16 gas block. Be sure to pick up the gas block coil pins for final assembly as well (430-103-127).

Fit 416 A1-A3 Models and US model MR556 rifles.

**Brownells recommend H1 or H2 recoil buffer with carbine recoil spring for optimal operation.

*** Brownells recommends use of 5.56x45mm NATO newly manufactured quality ammunition for optimal operation

Recommended Barrel Nut Torque: 50-80 ft/lbs

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4 Stars

2 Stars

Reviews Summary

Overall, reviewers appreciate the quality of the BRN-4 stripped barrels, noting their accuracy and chrome lining. However, several customers highlight issues with the gas port size, requiring modifications for reliable cycling. Despite this, many find the barrels nicely made and a good choice with some tinkering.

What Reviewers Are Saying

Product Quality

71%

Reviewers commonly praise the construction and aesthetics of the BRN-4 barrels, mentioning the chrome lining and overall accuracy as standout features. Many express satisfaction with the build quality, comparing it favorably to other well-known brands.

Gas Port Size Issues

43%

A significant theme revolves around the gas port size, with several reviewers stating that the port is undersized for reliable function with certain configurations. Most suggest modification is necessary to ensure smooth operation, which detracts from the user experience for some.

Drop-in Compatibility Concerns

43%

Many reviewers mention frustration regarding the expectation that these barrels would serve as drop-in replacements for specific rifles, particularly the HK416. The need for adjustments to fit properly has been a common point of criticism.

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Good barrels but need more options.

I'm really happy with the chromelined barrel. I ended up having a 14.5 cut to 11" by D Wilson. I hope in the future Brownells will offer additional barrel lengths like 11" ,12.5", 18 or maybe even the super rare 20". It would also be nice if the 14.5" had the grenade launcher cut to look more authentic.

Well done Brownells

I purchased this barrel as a spare for my HK MR556 because they refuse to give us chrome lined barrels. Had heard a few complaints of gas block index cut being off on some of them but my example was perfectly straight so Brownells must have taken care of the issue. On examination with a bore scope I was pleasantly surprised to see how nice the chrome lining and the rifling looked. Very similar to a factory Colt barrel. With match ammunition it prints around 1 moa. Well done Brownells.

by Chase on December 24, 2024

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Was this review helpful? 5

Great chrome lined barrel.

Lighter than my heavy HK barrel. I wish it had the full 416 profile with the 203 notch. The HK416 gass block slid on nice and easy. Now I have a spare barrel that's chrome lined.

by JAMES GORTHY on January 08, 2024

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Was this review helpful? 14

Undersized port

The barrel is decent quality, but the GT sport is undersized for use with the intended HK buffer and spring. Had to open up the gas port to .062 to get it to cycle reliably with 5.56 ammo.

Gas Port Undersized

Overall, this is a nice barrel. It didn't work as a drop in solution for a 416 though. I had to open up the gas port to .062" to get it to lock back on an empty mag with 5.56 62 grain ammo. I am using the factory HK buffer and Spring. Seems like these are ported to run with normal AR-15 carbine buffers (maybe?).

by JOHN ZELNA on March 17, 2024

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Was this review helpful? 16

Gas Porting

I got the 13.7" barrel. Overall, very nice accurate barrel. I had to open up the gas port to get it to cycle with an HK 416 Buffer and Spring, though. Once I opened it to .062" it cycles great with .223/5.56. With the factory porting it would not lock back with 62 grain FMJ 5.56 ammo. Hope this helps prospective buyers.

by John on March 17, 2024

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Was this review helpful? 13

Missed the mark

I bought the 13.7" Chrome Lined for my MR556. Im running an HK 16" Vented gas block and an HK Buffer and Spring. The Good: The barrel is nicely made and finished. The chrome lining and bore look great with my bore scope. The barrel is accurate with the ball ammo I have used so far. The Problems: The gas port is visibly smaller than my MR556 16" barrel gas port. I had D Wilson chop the 16" MR barrel to 14" a long time ago, and with no modifications that unlined MR barrel ran like a champ. My MR would basically eat any brass cased .223 or 5.56 without any problems. The BRN 4 barrel *Needs a larger gas port*. The 13.7 mine wont lock back on the last round reliably with 62 Grain PMC X Tac 5.56, and it wont cycle reliably with the bulk 223 brass cased ammo I have on hand. I plan on just drilling the gas port out myself to get it working, but it would be nice if a barrel advertised as an HK 416 replacement barrel worked on a factory HK rifle. Not a huge deal, but bear in mind you'll have to open up the port if you want to run it as a drop in on your HK. I thought about putting a regular AR buffer and spring in, but I just want this barrel to work on my HK the way it the gun was designed to work. Thoughts: I wish this was a drop in HK416 barrel that worked without mods to the base rifle. It will probably take some minor tinkering with your buffer system or gas port to get it working. Its a nice barrel. Brownells, if you read this: please just make proper the 14.5" M4 Profile Chrome Lined HK416 barrel that we all actually want!

by John on March 10, 2024

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All around bad.

The barrel has a bad defect where the gas block is so canted it touches the rail. Really bad quality control.