Let’s Talk About Cmmg, Inc Barrel Sub-Assm, 16in, 6mm ARC
The 6mm ARC (Advanced Rifle Cartridge) has taken the shooting world by storm, offering impressive ballistics and long-range capabilities in an AR-15 platform. Among the options for building your own 6mm ARC rifle, the Cmmg, Inc Barrel Sub-Assm, 16in, 6mm ARC stands out as a well-regarded choice from a reputable manufacturer. I’ve been building AR-platform rifles for over a decade, and the allure of the 6mm ARC’s performance in a standard AR lower piqued my interest.
I’ve been looking for a cartridge that offered a flatter trajectory and better wind resistance than the .223/5.56 NATO without sacrificing the AR-15’s modularity. The promise of sub-MOA accuracy and extended range from the 6mm ARC was exactly what I was after. After reading several positive reviews and watching a few comparison videos, I decided to give the Cmmg, Inc Barrel Sub-Assm, 16in, 6mm ARC a try.
Upon unboxing, I was immediately impressed with the fit and finish of the CMMG barrel. The barrel felt solid and well-made, and the SBN (Salt Bath Nitride) finish looked clean and durable. Compared to other budget-friendly barrel options I’ve used in the past, the CMMG barrel exuded a higher level of quality.
Initially, I was excited to get it installed and see how it performed. I had high expectations based on CMMG’s reputation and the 6mm ARC cartridge’s performance claims. My initial impression was very positive, and I couldn’t wait to get it to the range.
Real-World Testing: Putting Cmmg, Inc Barrel Sub-Assm, 16in, 6mm ARC to the Test
First Use Experience
I tested the Cmmg, Inc Barrel Sub-Assm, 16in, 6mm ARC at my local shooting range, which offers distances out to 300 yards. The weather was clear and mild, providing ideal conditions for testing accuracy. I used a variety of factory ammunition, including Hornady’s 108gr ELD Match and Speer’s 100gr BT.
The barrel performed admirably, producing consistent groups right out of the box. I did not experience any malfunctions or cycling issues during the initial break-in period. The rifle length gas system provided smooth recoil and reliable operation.
Extended Use & Reliability
After several months of use and approximately 500 rounds fired, the Cmmg, Inc Barrel Sub-Assm, 16in, 6mm ARC has proven to be reliable and accurate. I’ve taken it on several trips to the range and even used it during a varmint hunting trip. The barrel continues to hold its accuracy, and there are no signs of significant wear and tear.
Cleaning is straightforward, thanks to the Salt Bath Nitride finish, which resists carbon buildup. I’ve found that a quick scrub with a bore brush and some solvent is all it takes to keep the barrel in top condition. It definitely outperforms other barrels I’ve used in terms of ease of maintenance.
Breaking Down the Features of Cmmg, Inc Barrel Sub-Assm, 16in, 6mm ARC
Specifications
The Cmmg, Inc Barrel Sub-Assm, 16in, 6mm ARC features a 16-inch barrel length and is chambered in 6mm ARC. It is constructed from 416R Stainless Steel and features a Salt Bath Nitride finish for enhanced durability and corrosion resistance. The barrel profile is a Medium Taper, and it uses a Rifle Length gas system with a .750-inch gas block journal.
The 1-7.5 twist rate is optimized for stabilizing the longer, heavier bullets typically used in the 6mm ARC cartridge. These specifications translate to a balanced combination of accuracy, reliability, and manageable recoil in an AR-15 platform. The rifle length gas system contributes to smoother cycling and reduced felt recoil compared to shorter gas systems.
Performance & Functionality
The Cmmg, Inc Barrel Sub-Assm, 16in, 6mm ARC performs exceptionally well in terms of accuracy and reliability. With quality ammunition, it is capable of producing sub-MOA groups at 100 yards. The rifle length gas system ensures reliable cycling and smooth recoil, making it comfortable to shoot even during extended range sessions.
The only slight weakness I’ve noticed is that some lighter weight bullets (under 90 grains) are not as consistently accurate as the heavier options. Overall, the barrel meets and exceeds my expectations for a mid-priced AR barrel.
Design & Ergonomics
The Cmmg, Inc Barrel Sub-Assm, 16in, 6mm ARC is well-designed and feels solid in hand. The 416R Stainless Steel construction and SBN finish give it a durable and high-quality feel. Installing the barrel was straightforward, and it fit perfectly into my upper receiver.
There is minimal learning curve to using this barrel. As long as you’re familiar with AR-15 platform rifles, you’ll find it easy to operate and maintain.
Durability & Maintenance
The Salt Bath Nitride finish provides excellent corrosion resistance and makes the barrel easy to clean. After 500 rounds, there are no signs of significant wear or damage. With proper care and maintenance, this barrel should provide many years of reliable service.
Cleaning is simple; a bore brush and solvent are all that’s needed to remove carbon buildup. The SBN finish makes it easier to clean than standard stainless steel barrels.
Accessories and Customization Options
The Cmmg, Inc Barrel Sub-Assm, 16in, 6mm ARC is compatible with any standard AR-15 upper receiver and gas block. It readily accepts aftermarket muzzle devices, such as suppressors and brakes, due to its standard threading. The .750 gas block journal is also a very common size, which means that users can find lots of compatible accessories.
Given the 6mm ARC chambering, proper magazines are a must. While 5.56 magazines might feed rounds, they were not designed for the ARC and can cause issues. Lancer and ASC make great 6mm ARC magazines, but be sure to confirm compatibility before purchasing.
Pros and Cons of Cmmg, Inc Barrel Sub-Assm, 16in, 6mm ARC
Pros
- Excellent accuracy: Capable of sub-MOA groups with quality ammunition.
- Reliable cycling: Rifle length gas system ensures smooth and consistent operation.
- Durable construction: 416R Stainless Steel with Salt Bath Nitride finish for long-lasting performance.
- Affordable price: Provides excellent value for the money.
- Easy to clean: SBN finish simplifies maintenance.
Cons
- Can be ammunition sensitive. The best accuracy achieved with heavier projectiles.
- 6mm ARC ammunition is currently more expensive and harder to find than 5.56 NATO.
Who Should Buy Cmmg, Inc Barrel Sub-Assm, 16in, 6mm ARC?
The Cmmg, Inc Barrel Sub-Assm, 16in, 6mm ARC is perfect for shooters looking to build an accurate and reliable AR-15 for long-range target shooting or varmint hunting. It is an excellent choice for those who appreciate the benefits of the 6mm ARC cartridge, such as its flat trajectory and resistance to wind drift. This barrel is a great choice for someone wanting a simple drop-in solution.
Those who primarily shoot inexpensive bulk ammunition or are on a very tight budget may want to consider a different caliber, such as 5.56 NATO or .223 Wylde. Someone wanting to do extreme long range shooting might be better served with a longer barrel offering increased velocity. A quality optic is a must-have accessory to take advantage of the Cmmg, Inc Barrel Sub-Assm, 16in, 6mm ARC‘s accuracy potential.
Conclusion on Cmmg, Inc Barrel Sub-Assm, 16in, 6mm ARC
The Cmmg, Inc Barrel Sub-Assm, 16in, 6mm ARC is a well-made and accurate barrel that offers excellent value for the price. Its reliability, durability, and ease of maintenance make it a great choice for both experienced and novice AR-15 builders. The price is definitely justified given the performance and quality you receive.
I would highly recommend the Cmmg, Inc Barrel Sub-Assm, 16in, 6mm ARC to anyone looking to build a 6mm ARC AR-15. If you’re seeking a reliable, accurate, and affordable barrel for your next build, look no further. Experience the 6mm ARC difference for yourself!