Nefarious Arms HK416 / MR556 Barrel, 10.4" HEAVY, 5.56x45mm NATO
Nefarious Arms HK416 / MR556 Barrel, 10.4" HEAVY, 5.56x45mm NATO
27 in stock
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The Nefarious Arms HK416 / MR556 Barrel is engineered for shooters who demand uncompromising performance, precision, and durability. Proudly made in the USA, this barrel is crafted from premium 4150 Chrome Moly steel, cold-hammer-forged for strength, and chrome-lined to ensure years of reliable accuracy. Finished in black manganese phosphate, it’s built to handle heavy use while maintaining peak performance. Whether you’re upgrading your HK416 or MR556, or this barrel delivers the reliability and consistency you can trust.
Key Features:
- Caliber: 5.56x45mm NATO
- Barrel Length: 10.4"
- Profile: HEAVY
- Twist Rate: 1:7
- Barrel Extension: A1/A3
- Gas Block Seat Diameter: 19mm (h6 Tolerance)
- Muzzle Threads: 1/2"x28
- Material: 4150 Chrome Moly
- Finish: Black Manganese Phosphate
- Cold-Hammer-Forged for Strength and Consistency
- Chrome-Lined for Years of Accurate Shooting
-
Weight: 26 oz.
- Made in USA 🇺🇸
Compatible With:
- HK416 A1/A3
- HK MR556
Compatible Gas Blocks:
- HK A1/A3
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Let customers speak for us
from 26 reviewsHelps immensely when pushing pins. Keeps everything stable and easy to work with. Keeps you from marring your barrels!
Gives me the confidence to work on my 416 platform gun without damaging anything. Works on multiple platforms as well.
Folding sight arrived in great shape. Works with my 33mm height rear just fine. A+
Awesome tool! Its well made, helps with working on yhe 416 platform specifically. Great finish too.
Same ol’ great NA quality we’ve all come to expect. Super cool threads!
For those who don’t already know, you CANNOT do better than Marvin’s barrels. Or pretty much anything Marvin makes. Spend some money, buy his stuff, own great sh*t.
Quality item. Machine work is flawless. Best HK barrel you can find brand new.
Great hard to find unmarked HK upper. Super fast shipping too!
No issues with installation. Was easy to just, just took a little time to try the different jets. You need to make a version for the MR762.
It is nice to do business with a company that provides impeccable customer service along with quality products. Very happy with my purchase of the HK 416 reaction rod.
It's always nice to have the right tool for the job. This reaction rod is precision made from quality materials and meets HK's exacting tolerances without damaging the barrel.
So far so good. Fits great! Great products! Been running there barrels for a couple years!