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 51 reviewsNothing but the best.
Wow! I'm so glad I was able to grab the last SOCOM profile 14.5 A5 barrel available for now. IMO the fit and the finish is top notch and can't be matched.
I shot nice thight groups out to 100m... so, I can't complain. Looking back, I wish, I could have gotten at least one more barrel for a future A5 project.
Alan Taylor
Dallas, Texas
Very high quality barrel. I would consider this to be as good if not better than the hk made barrels. The chrome lining is excellent and the overall fit and finish is top class. Very smooth shooting would definitely recommend if you are wanting to build a clone or just looking for a high quality cold hammer forged chrome line barrel.
Just got it last Friday so I haven't shot it yet. I purchased the barrel and had Marvin install it on an MR556A4 upper. The work looks really good (no little nicks or anything), the barrel itself is well-made and it's nice seeing a chrome-lined barrel on an HK MR carbine! Would definitely recommend Marvin's work as well as NA for offering us "civvies" a mil-spec barrel. Kudos!
P.S.- Holly answers the phones there and she was very helpful and polite. You all have a solid employee!
Very high quality and definitely adds pressure to the system.
Excellent option for the MR556A4 and 416 clones.
Marvin and his products are top notch. Perfect fitment, excellent quality. These are the best barrels outside fo factory HK that one can buy!
For your barrel nut torquing a must have precision made tool. Excellent machined quality to use on a number of AR , KAC , Centurion Arms or HK variants.
Nicer than other popular and similar tools I have. protect your barrel extension index pin! Get one!