First Impressions of CMMG 6.5 Grendel 16in Barrel Sub-Assm
The CMMG 6.5 Grendel 16in Barrel Sub-Assm promises to be a cornerstone for any AR-15 enthusiast looking to venture into the realm of 6.5 Grendel. CMMG is a known brand with great quality products that could elevate any build. This sub-assembly offers an enticing blend of quality materials, precise specifications, and the potential for exceptional performance, all at a competitive price point.
For years, I’d been limited to the standard 5.56 NATO, always yearning for a cartridge with better long-range ballistics and terminal performance for deer hunting. The 6.5 Grendel always piqued my interest, with its promise of flatter trajectories and greater energy on target, so building a dedicated upper receiver group was the next logical step. I initially considered a complete upper but decided that assembling my own would be a learning experience and allow for greater customization down the road.
The sub-assembly arrived well-packaged. My initial impression was positive. The salt bath nitride finish looked clean and even, while the 416 stainless steel hinted at durability and resistance to the elements. I held it up and thought about the possibilities.
I was torn between this and a similar offering from Brownells and a higher-end option from Lilja. Ultimately, the price and the reputation of CMMG swayed me. I was excited to finally begin my 6.5 Grendel journey.
Real-World Testing: Putting CMMG 6.5 Grendel 16in Barrel Sub-Assm to the Test
First Use Experience
My initial testing took place at my local shooting range, a controlled environment where I could focus on accuracy and function. The weather was mild, around 65 degrees Fahrenheit, with a slight breeze. I mounted the CMMG 6.5 Grendel 16in Barrel Sub-Assm onto a spare lower receiver, slapped in a magazine loaded with Hornady Black 123gr ELD Match ammunition, and settled behind the bench.
The first few rounds felt smooth. The rifle-length gas system tamed the recoil effectively. The rifle digested the ammunition well, with no failures to feed or eject. I shot groups at 100 yards, and I was immediately impressed.
There weren’t any real surprises, aside from the surprisingly manageable recoil.
Extended Use & Reliability
After several months and over 500 rounds through the CMMG 6.5 Grendel 16in Barrel Sub-Assm, I can confidently say it’s holding up exceptionally well. I have been using it for hunting varmints mostly. There are no noticeable signs of wear and tear. The nitride finish still looks new, even after a few hunts in brushy terrain.
Cleaning is straightforward. The salt bath nitride finish makes removing carbon fouling relatively easy, with just a few passes of a bore brush and some solvent. Proper care is the key.
Compared to my previous AR-15 barrel, which was a standard chrome-lined 5.56, the CMMG barrel offers significantly better accuracy and consistency. It has exceeded my expectations.
Breaking Down the Features of CMMG 6.5 Grendel 16in Barrel Sub-Assm
Specifications
Caliber: 6.5 Grendel, offering superior ballistic performance and long-range capabilities compared to 5.56 NATO. The 6.5 Grendel is a very potent round.
Barrel Length: 16 inches, providing a good balance between maneuverability and velocity. This allows for both close range maneuvering and accuracy at longer distances.
Material: 416 Stainless Steel, chosen for its durability, corrosion resistance, and potential for accuracy. Stainless steel has great overall qualities.
Finish: Salt Bath Nitride, which hardens the surface, reduces friction, and enhances corrosion resistance. This creates a very durable and lasting finish.
Barrel Profile: Medium Tapered, striking a balance between weight savings and rigidity. The barrel doesn’t overheat as quickly.
Gas System Length: Rifle Length, providing a smoother recoil impulse and reduced wear on components compared to shorter gas systems. Rifle length gas systems make the shooting experience very smooth.
Gas Block Journal Size: .750 inches, a standard size for AR-15 barrels, allowing for compatibility with a wide range of gas blocks. This allows for a wide array of customization.
Threads Per Inch: 5/8×24, the standard thread pitch for 6.5 Grendel barrels, ensuring compatibility with most muzzle devices. Most muzzle devices will work with this thread pitch.
Barrel Twist Rate: 1-8, optimized for stabilizing a wide range of 6.5 Grendel bullet weights. This twist rate is considered ideal for the 6.5 Grendel.
Weight: 1.55 lb, a moderate weight that doesn’t significantly add to the overall rifle weight. The rifle is easy to carry without being too heavy.
Performance & Functionality
The CMMG 6.5 Grendel 16in Barrel Sub-Assm excels in accuracy and reliability. With quality ammunition, sub-MOA groups are achievable.
Its primary strength lies in its ability to deliver consistent and accurate performance, with minimal recoil. A potential area for improvement might be offering a threaded muzzle with a included thread protector. It meets my expectations and is great.
Design & Ergonomics
The barrel’s medium tapered profile strikes a good balance between weight and rigidity. The build quality feels robust and reliable, giving me confidence in its long-term durability.
It is extremely user-friendly. The barrel installs seamlessly into any standard AR-15 upper receiver.
Durability & Maintenance
Given its 416 stainless steel construction and salt bath nitride finish, I expect this barrel to last for thousands of rounds with proper care. Cleaning is simple. Regular cleaning will help it last a long time.
Accessories and Customization Options
The CMMG 6.5 Grendel 16in Barrel Sub-Assm readily accepts standard AR-15 accessories. The .750 gas block journal size accommodates most aftermarket gas blocks.
Given the 5/8×24 thread pitch, a wide range of muzzle devices, such as compensators and suppressors, can be easily installed. This is great for customization and to fit the users’ preferences.
Pros and Cons of CMMG 6.5 Grendel 16in Barrel Sub-Assm
Pros
- Excellent Accuracy: Capable of sub-MOA groups with quality ammunition.
- Smooth Recoil Impulse: The rifle-length gas system makes for a comfortable shooting experience.
- Durable Construction: 416 Stainless Steel and a salt bath nitride finish ensure long-lasting performance.
- Versatile Caliber: The 6.5 Grendel offers superior ballistics for hunting and long-range shooting.
- Easy Maintenance: The nitride finish makes cleaning relatively simple.
Cons
- No muzzle device included.
- Lacks fluting for enhanced cooling.
Who Should Buy CMMG 6.5 Grendel 16in Barrel Sub-Assm?
The CMMG 6.5 Grendel 16in Barrel Sub-Assm is perfect for hunters seeking a more capable AR-15 platform for medium-sized game. Long-range shooters will benefit from the cartridge’s flatter trajectory and reduced wind drift. It is also great for AR-15 enthusiasts who enjoy building and customizing their rifles.
Those strictly focused on close-quarters combat or those who prioritize lightweight builds might find other options more suitable. A quality optic is a must-have accessory to fully realize the barrel’s accuracy potential. A bipod or shooting rest will also aid in precision shooting.
Conclusion on CMMG 6.5 Grendel 16in Barrel Sub-Assm
The CMMG 6.5 Grendel 16in Barrel Sub-Assm is a high-quality component that delivers exceptional performance at a reasonable price. Its accuracy, reliability, and durable construction make it a worthwhile investment for anyone looking to upgrade their AR-15 platform.
The $163.38 price tag is justified by the quality materials and performance. I would absolutely recommend it.
If you’re looking to build a 6.5 Grendel AR-15, this barrel sub-assembly is an excellent place to start!