NBS 20" 6mm ARC 4150 Rifle Medium 1:7.5 Twist Nitride Barrel - 6ARCR20MED50B7.5T2
In stock
Elevate your AR-15 build with the precision-engineered 20″ 6mm ARC 4150 Rifle Medium 1:7.5 Twist Nitride Barrel, designed for long-range accuracy and reliable performance. This barrel harnesses the power of the 6mm ARC cartridge, delivering exceptional ballistics in a compact AR platform. Whether you’re a competitive shooter or a dedicated hunter, this medium-profile barrel offers the perfect balance of weight, durability, and velocity retention for shots beyond 800 yards.
Key Features
- Premium 4150 Chrome Moly Vanadium Steel: Ensures superior strength and heat resistance, standing up to high-volume fire without compromising accuracy.
- Nitride/Melonite Finish: Provides corrosion resistance and reduces friction for smoother operation and extended barrel life.
- 1:7.5 Twist Rate: Optimally stabilizes heavier 6mm ARC projectiles (80-108 grains), maximizing downrange performance and wind resistance.
- Rifle-Length Gas System: Promotes smoother cycling and reduced recoil, ideal for precision setups.
- 5/8×24 Muzzle Threads: Compatible with a wide range of suppressors and muzzle devices to customize your setup.
Specifications
- Barrel Length: 20 inches
- Caliber: 6mm ARC
- Profile: Medium
- Gas Block Journal: 0.75 inches
- Platform: AR-15
- Weight: 26 ounces
- Finish: Nitride
Why Choose This 6mm ARC Barrel?
Struggling with inconsistent accuracy or excessive barrel weight in your AR-15? This 20-inch 6mm ARC barrel solves those issues by combining a medium contour for manageable carry weight with the rigidity needed for sub-MOA groups at extended ranges. The 4150 steel construction withstands rigorous training sessions, while the nitride treatment minimizes fouling for quicker cleanings and consistent shot-to-shot performance. Users appreciate how it transforms standard AR platforms into versatile long-range tools, outperforming traditional 5.56 setups in ballistics without the bulk of larger calibers. Perfect for varmint hunting, PRS competitions, or tactical applications where precision matters most.
Ready to upgrade your rifle? Invest in this high-quality AR-15 6mm ARC barrel today and experience the difference in your next range day or field outing.
Frequently Asked Questions
1. What bolt carrier group is compatible with this barrel?
This barrel requires a bolt with a 6.5 Grendel Type 2 bolt face for proper function with 6mm ARC ammunition.
2. Is this barrel a drop-in replacement for my AR-15?
Yes, it’s designed as a direct fit for AR-15 upper receivers, but ensure your gas system matches the rifle-length configuration for optimal reliability.
3. What ammunition performs best in this 1:7.5 twist barrel?
Heavier bullets from 80 to 108 grains excel, providing excellent stability and long-range accuracy with factory or handloaded 6mm ARC loads.
NBS — Our In-House Brand for Builders Who Demand Reliable Performance and Real Value.
Designed for builders who demand reliable performance and real value without unnecessary hype or inflated pricing. NBS stands for "No Bullshit."
Built on Strong Industry Partnerships
Through the strong partnerships AR15Discounts has built with trusted suppliers and vendors, we regularly gain access to premium components often manufactured by or for leading industry names. By purchasing these in volume, we bring them to you under the NBS label, ensuring proven quality reaches your build at a fair price, without the added cost of extensive marketing.
Quality You Can Trust
Every NBS product is specified to the exacting standards we apply to our own rifles. Each component features precision CNC machining, American-made key components where it counts, robust materials, dependable steels, and durable finishes engineered for long-term reliability. These items are either sourced from reputable OEMs or carefully assembled in-house using established name-brand elements, maintaining consistent excellence throughout the lineup.
Complete Solutions for Serious Builders
From stripped and complete uppers to bolt carrier groups, handguards, lower parts kits, and beyond, NBS provides a unified, affordable selection that allows you to complete confident, high-performing builds.
Backed by a Limited Lifetime Warranty
All NBS products come with our Limited Lifetime Warranty for the original owner, covering defects in materials and workmanship. AR15Discounts stands firmly behind these parts because, as shooters ourselves, we use and trust them, delivering honest value and gear you can rely on.
| Weight | 26 oz |
|---|---|
| Dimensions | 22 × 3 × 3 in |
| Finish | Nitride / Melonite |
| Barrel Profile | Medium |
| Cartridge Compatibility | 6mm ARC |
| Gas Block Journal | 0.75 |
| Barrel Length | 20 |
| Gas System Length | Rifle |
| Platform | AR-15 |
| Twist Rate | 1:7.5 |
| Muzzle Thread Pattern | 5/8×24 |
| MPN | 6ARCR20MED50B7.5T2 |
| UPC | 28364 |
Compliance
NFA (National Firearms Act) compliance is crucial for legal ownership and transfer of regulated firearms and accessories like short-barreled rifles, suppressors, and certain types of ammunition, ensuring adherence to federal regulations to avoid legal penalties and ensure responsible firearm ownership.
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Freaking laser beams!
On sale, this is a great value. Loaded with Factory Hornady Match 108 ELDMs, this barrel is more than worthy. My set up is very budget oriented, I definitely fought the basic PSA lower build kit’s trigger trying to get these groups, I kept pulling one or two. A better trigger will shrink the group further, I hope! Otherwise, these groups were more than satisfactory after only two box’s of ammo through the tube. I look forward to stretching out further, knowing it groups this well at 100. Awesome job bringing an amazing valued 6mm ARC barrel to the AR building community AR15discounts.com! If you are reading this and this barrel is on sale closer to $100, just click purchase!
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