Nefarious Arms Barrel, 14.5" M4 E3 Heavy SOCOM with KAC E3 Barrel Extension, 5.56x45mm
Nefarious Arms Barrel, 14.5" M4 E3 Heavy SOCOM with KAC E3 Barrel Extension, 5.56x45mm
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Built for accuracy, built for hard use — this 14.5" M4 E3 Heavy SOCOM barrel delivers dependable performance shot after shot.
This 14.5" 5.56×45mm Heavy M4 SOCOM-profile barrel is designed for shooters who demand precision and durability. Whether you're building a duty rifle, range gun, or modern M4 SOCOM-style carbine, this barrel gives you the consistency and reliability needed for serious performance.
Key Features:
- 14.5" Knights Armament M4 Heavy SOCOM-profile barrel
- Chambered in 5.56×45mm NATO
- Optimized for accuracy and repeatable performance
- Hammer Forged for durable construction for hard-use builds
- Chrome-Lined Bore
- Ideal for M4 SOCOM-style and duty-grade rifles
- M203 "KAC" Style Cut
- Twist Rate: 1:7
- Gas Block Seat Diameter: 0.750" x 2"
- Gas System Length: Carbine-Length
- Muzzle Threads: 1/2"x28 TPI
- SR-15/SR-16 E3 Barrel Extension (#21089-1) Sourced from Knights Armament
- M4 Feed Ramps
- Heavy Manganese Phosphate
- Made in USA by Nefarious Arms
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from 62 reviewsA hard to find item which you had in stock. Order placed in the am and shipped the same day. Quality parts and outstanding service!
Shipped same day and was exactly as described! Yall are awesome! Cant wait to buy more stuff!
Heavy duty and well machined.
This company is great! Marvin is an artist, orders sometimes will take a while but rest assured when you do get it, it will be perfect, so if youre a potential customer, be patient. It will be done
I enjoyed all the products so far. I plan to purchase more products in the future, keep up the good work!
I used this tool to build a Nefarious Arms A3 IAR barrel on an MR556 upper, and it was absolutely perfect for the job. It easily held under the required torque specs with zero barrel shift. More importantly, it eliminated any worry about shearing off the index pin, ensuring near-perfect timing after installation.Before this, I attempted to use a Midwest Industries Reaction Rod but found way too much play. The MR556 platform demands tight tolerances, and a generic reaction rod simply doesn't offer the precision needed. Because this tool is made specifically for these barrels, the fit is exact. If you are doing an MR556 build, this is the tool you need.