First Impressions of CMMG 30BC40AMB Resolute MK4 300 Blackout 16.10″, Midnight Bronze, M-LOK Free-Flo
The CMMG 30BC40AMB Resolute MK4 300 Blackout 16.10″, Midnight Bronze, M-LOK Free-Flo is a meticulously crafted upper receiver group designed to enhance any AR-15 lower receiver. CMMG has built a solid reputation for quality AR platform components, and this Resolute MK4 in 300 Blackout is no exception. The sleek Midnight Bronze finish immediately sets it apart, while the M-LOK free-float handguard suggests modern versatility. This upper promises a blend of aesthetics, performance, and modularity that’s sure to appeal to a wide range of shooters.
I was searching for a dedicated 300 Blackout upper to pair with a spare AR-15 lower I had lying around. I wanted something reliable, accurate, and aesthetically pleasing without breaking the bank. I was drawn to this CMMG offering because of its reputation for quality and the attractive Midnight Bronze finish.
My initial impression upon unboxing was highly positive. The finish is flawless, the weight feels balanced, and the M-LOK handguard appears robust. The upper feels solid and well-assembled, lending an immediate sense of confidence.
I considered the Aero Precision M4E1 Enhanced Upper and the Bravo Company BCM MK2 Upper Receiver Group. I ultimately chose the CMMG due to its unique color, positive reviews regarding its barrel quality, and the fact that I’ve had good experiences with CMMG products in the past. The price point, while not the absolute lowest, felt justified given the overall package.
I was definitely excited. The CMMG 30BC40AMB Resolute MK4 300 Blackout 16.10″, Midnight Bronze, M-LOK Free-Flo looks and feels like a high-quality piece of equipment. I was eager to get it out to the range and see how it performs.
Real-World Testing: Putting CMMG 30BC40AMB Resolute MK4 300 Blackout 16.10″, Midnight Bronze, M-LOK Free-Flo to the Test
First Use Experience
My first outing with the CMMG 30BC40AMB Resolute MK4 300 Blackout 16.10″, Midnight Bronze, M-LOK Free-Flo was at an outdoor shooting range. I tested it with both supersonic and subsonic ammunition to get a feel for its versatility. The weather was clear and relatively mild, around 65 degrees Fahrenheit with a light breeze.
The upper performed flawlessly with both types of ammunition. There were no failures to feed, fire, or eject. The recoil was manageable, even with the supersonic rounds, and the accuracy was impressive right out of the box.
The upper was easy to install on my existing lower receiver and required no modifications. I did not need time to get used to it; it felt natural and comfortable from the start.
There were no issues or surprises after the first use, other than being extremely impressed with its overall performance. The rifle cycled smoothly and accurately.
Extended Use & Reliability
After several months of regular use, the CMMG 30BC40AMB Resolute MK4 300 Blackout 16.10″, Midnight Bronze, M-LOK Free-Flo continues to impress. It’s been through multiple range sessions, including some drills in slightly dusty conditions. The reliability has been unwavering.
There are minimal signs of wear and tear. The Midnight Bronze finish has proven to be quite durable. It has held up well against scratches and minor abrasions from handling and transportation.
Maintenance is straightforward. Regular cleaning and lubrication are all that’s needed to keep it running smoothly. The barrel cleans easily, and the BCG shows no signs of excessive wear.
Compared to some other uppers I’ve used, the CMMG definitely outperforms in terms of accuracy and reliability. Its smooth cycling and consistent performance have made it one of my favorite AR configurations.
Breaking Down the Features of CMMG 30BC40AMB Resolute MK4 300 Blackout 16.10″, Midnight Bronze, M-LOK Free-Flo
Specifications
- Manufacturer: CMMG. Known for quality AR components.
- Caliber: .300 AAC Blackout. Offers versatility for both supersonic and subsonic rounds.
- Barrel Length: 16.10 inches. Provides a good balance of maneuverability and ballistic performance.
- Finish: Midnight Bronze. Aesthetically pleasing and adds a layer of corrosion resistance.
- Color: Midnight Bronze. Stands out from typical black ARs.
- Gun Make: AR Platform. Compatible with any standard AR-15 lower receiver.
- Gun Model: AR-15. Designed as an upper receiver group for AR-15 pattern rifles.
- Additional Features: M-LOK Free-Float. Allows for easy attachment of accessories and enhances accuracy.
- Condition: New. Arrives in pristine, ready-to-use condition.
- Magazine Included: No. Requires separate purchase of 300 Blackout magazines.
These specifications are significant because they determine the overall performance and usability of the upper. The 300 Blackout caliber provides versatility, the 16.1-inch barrel is a good compromise between length and maneuverability, and the M-LOK handguard enables customization. The Midnight Bronze finish adds a touch of class and durability.
Performance & Functionality
The CMMG 30BC40AMB Resolute MK4 300 Blackout 16.10″, Midnight Bronze, M-LOK Free-Flo performs exceptionally well. The accuracy is excellent, with consistent groupings at 100 yards. Reliability is top-notch, with no malfunctions experienced during testing.
The strengths lie in its smooth cycling, accurate barrel, and durable finish. One potential area for improvement would be the inclusion of a forward assist, though this is a minor point.
The upper meets and exceeds expectations. It delivers consistent performance and is a pleasure to shoot.
Design & Ergonomics
The build quality is outstanding. The materials used are high-grade, and the fit and finish are excellent. The weight is well-balanced, making the rifle comfortable to handle.
It’s very user-friendly. Installation is simple, and the M-LOK handguard allows for easy customization. There is no significant learning curve.
Durability & Maintenance
With proper care, the CMMG 30BC40AMB Resolute MK4 300 Blackout 16.10″, Midnight Bronze, M-LOK Free-Flo should last for many years. The durable finish and high-quality components ensure longevity.
Maintenance is easy. Regular cleaning and lubrication are all that’s required.
Accessories and Customization Options
The upper comes ready to accept a wide variety of accessories. The M-LOK handguard allows for easy attachment of lights, lasers, foregrips, and other tactical accessories.
The upper is compatible with most AR-15 accessories, including optics, sights, and slings. The user can easily customize the rifle to their specific needs and preferences.
Pros and Cons of CMMG 30BC40AMB Resolute MK4 300 Blackout 16.10″, Midnight Bronze, M-LOK Free-Flo
Pros
- Exceptional Accuracy: The barrel provides consistent and tight groupings.
- High Reliability: Functions flawlessly with both supersonic and subsonic ammunition.
- Durable Finish: The Midnight Bronze finish is aesthetically pleasing and resistant to wear.
- M-LOK Handguard: Allows for easy attachment of accessories and customization.
- Easy Installation: Installs easily on any standard AR-15 lower receiver.
Cons
- No Magazine Included: Requires separate purchase of 300 Blackout magazines.
- Lack of Forward Assist: Some users may prefer having a forward assist.
Who Should Buy CMMG 30BC40AMB Resolute MK4 300 Blackout 16.10″, Midnight Bronze, M-LOK Free-Flo?
Perfect for: Hunters seeking a versatile platform for both suppressed subsonic and supersonic rounds, tactical shooters looking for a reliable and accurate upper receiver, and AR enthusiasts who appreciate quality and aesthetics. It’s also great for home defense, given the 300 Blackout’s effectiveness in close quarters.
Who should skip this product? Someone on an extremely tight budget might find cheaper options. If you absolutely require a forward assist, this upper might not be for you.
Must-have accessories or modifications? A quality optic (red dot or scope), a good sling, and a supply of reliable 300 Blackout magazines. A suppressor is highly recommended to take full advantage of the 300 Blackout’s subsonic capabilities.
Conclusion on CMMG 30BC40AMB Resolute MK4 300 Blackout 16.10″, Midnight Bronze, M-LOK Free-Flo
The CMMG 30BC40AMB Resolute MK4 300 Blackout 16.10″, Midnight Bronze, M-LOK Free-Flo is an outstanding upper receiver group that delivers exceptional performance, reliability, and aesthetics. The Midnight Bronze finish and M-LOK handguard make it a standout choice.
The price is justified given the quality of the components and the overall performance. It offers a great value proposition for those seeking a high-quality 300 Blackout upper.
I would highly recommend it. The CMMG 30BC40AMB Resolute MK4 300 Blackout 16.10″, Midnight Bronze, M-LOK Free-Flo is a top-tier choice that will not disappoint. If you’re looking to build or upgrade your AR-15 with a dedicated 300 Blackout upper, this is an excellent option to consider.