Let’s Talk About Radical Firearms RF Upper Assembly 8.5in 300 AAC HBAR Contour w/ A2 Flash Hider
The Radical Firearms RF Upper Assembly 8.5in 300 AAC HBAR Contour w/ A2 Flash Hider is a compelling option for AR pistol or SBR builds, especially for those looking for a compact and potent package in the versatile 300 AAC Blackout caliber. This upper receiver assembly provides a solid foundation for a reliable and accurate firearm, featuring a free-float rail system and durable construction. It’s designed to be easily installed on any MIL-STD lower receiver, making it a great choice for both experienced builders and newcomers venturing into the world of AR customization.
I’ve been searching for a compact upper receiver in 300 Blackout for a dedicated home defense build, something maneuverable yet capable of delivering serious stopping power. The appeal of the 300 Blackout lies in its ability to be effective in short barrels, and its versatility with both subsonic and supersonic ammunition.
Upon unboxing, the Radical Firearms upper struck me as robust and well-assembled. The finish, while basic, seemed even and durable. The 7″ free float rail felt solid and provided ample space for mounting accessories. It’s a no-frills, purpose-built design.
I considered options from Aero Precision and Ballistic Advantage, both known for their quality, but the Radical Firearms upper offered a more budget-friendly entry point without sacrificing essential features. I chose it primarily for its price point and the established reputation of Radical Firearms in the AR parts market.
My initial impression was positive. It’s a simple, functional upper that feels like it will perform as intended. While the finish might not be the most refined, the overall build quality seems solid enough for a workhorse firearm.
Real-World Testing: Putting Radical Firearms RF Upper Assembly 8.5in 300 AAC HBAR Contour w/ A2 Flash Hider to the Test
First Use Experience
I took the Radical Firearms upper to my local indoor shooting range to zero my optic and test its functionality. I primarily used supersonic 110-grain V-MAX ammunition for initial testing, alongside some 220-grain subsonic rounds.
The upper performed reliably through the first 100 rounds. There were no malfunctions or issues with cycling, even with the change in ammunition type (supersonic to subsonic). It was relatively easy to get accurate shots on target, although the short barrel did produce a noticeable muzzle flash.
The only slight issue was that the A2 flash hider wasn’t particularly effective at mitigating muzzle flash with supersonic rounds, but that’s a known limitation of the A2 design.
Extended Use & Reliability
After several months of use, with approximately 500 rounds through the Radical Firearms upper, it has proven to be quite reliable. The finish has held up well, with only minor wear marks in high-friction areas.
Maintenance has been straightforward, requiring only regular cleaning and lubrication after each range session. The free-float rail design made it easy to clean the barrel and gas system.
Compared to my previous experiences with budget AR uppers, the Radical Firearms performed admirably. It’s not a high-end, match-grade upper, but it delivers consistent and reliable performance for its intended purpose. It certainly exceeded my expectations.
Breaking Down the Features of Radical Firearms RF Upper Assembly 8.5in 300 AAC HBAR Contour w/ A2 Flash Hider
Specifications
- Caliber: .300 AAC Blackout. This caliber is known for its effectiveness in short-barreled rifles (SBRs) and AR pistols, making it a popular choice for close-quarters combat and home defense.
- Barrel Length: 8.5 inches. This short barrel length enhances maneuverability, making it ideal for tight spaces, while still maintaining sufficient velocity for the 300 Blackout cartridge to perform effectively.
- Barrel Profile: HBAR Contour. The HBAR (Heavy Barrel) contour provides added rigidity and heat dissipation, improving accuracy during sustained fire.
- Gas System Length: Pistol Length. The pistol-length gas system is optimized for shorter barrels, ensuring reliable cycling.
- Barrel Twist Rate: 1-7 or 1-8 (verify before purchase). The twist rate stabilizes a wide range of bullet weights, from lightweight supersonic rounds to heavier subsonic rounds. Note: Some users report the twist rate to be 1:8, not 1:7 as older descriptions may state, so confirm before purchasing if the twist rate is critical.
- Threads per Inch: 5/8×24. This is the standard thread pitch for .30 caliber barrels, allowing for compatibility with a wide variety of muzzle devices and suppressors.
- Handguard Type: Free-Float. Free-float handguards do not contact the barrel, improving accuracy by minimizing vibrations and allowing for consistent barrel harmonics.
- Muzzle Device: A2 Flash Hider. The A2 flash hider is a common and affordable muzzle device that reduces muzzle flash, though it is not the most effective option for this purpose.
- Finish: Anodized. The anodized finish provides a durable and corrosion-resistant coating to the aluminum components.
- Handguard Length: 7 inches. The 7-inch handguard provides ample space for mounting accessories while maintaining a compact profile.
- Handguard Style: Round Rail. The round rail provides a comfortable grip and allows for easy attachment of accessories at various positions.
- Gun Rail: M-LOK. The M-LOK rail system allows for direct attachment of M-LOK compatible accessories, providing a secure and lightweight mounting solution.
- Barrel Material: 4140 Chrome Moly Vanadium. 4140 CMV steel is a durable and reliable barrel material that is commonly used in AR-15 barrels.
These specifications contribute to the upper’s overall performance by providing a balance of maneuverability, accuracy, and reliability. The short barrel and pistol-length gas system make it well-suited for close-quarters applications, while the HBAR contour and free-float handguard enhance accuracy.
Performance & Functionality
The Radical Firearms RF Upper Assembly 8.5in 300 AAC HBAR Contour w/ A2 Flash Hider performs its intended function as a reliable and compact upper receiver assembly. Accuracy is acceptable for its intended use, achieving roughly 2-3 MOA with quality ammunition.
Its strengths lie in its compatibility, ease of installation, and consistent cycling. The main weakness is the basic finish, which may not appeal to those seeking a more aesthetically refined product.
Overall, it meets expectations for a budget-friendly 300 Blackout upper.
Design & Ergonomics
The build quality is decent for the price point. The materials used are standard for AR-15 components, and the assembly feels solid.
The round rail is relatively comfortable to hold, and the M-LOK system provides ample space for attaching accessories. The upper is relatively user-friendly, requiring no specialized knowledge to install and operate.
Durability & Maintenance
With proper care and maintenance, the Radical Firearms upper should last for a significant number of rounds. The anodized finish helps to protect against corrosion, and the 4140 CMV barrel is relatively durable.
Maintenance is simple, requiring only regular cleaning and lubrication.
Accessories and Customization Options
The upper assembly comes with a 7″ Hybrid Rail System – MHR. It is compatible with a wide range of AR-15 accessories, including optics, lights, lasers, and foregrips.
The standard 5/8×24 threads allow for the use of various muzzle devices and suppressors. The M-LOK rail system provides a wide range of mounting options for accessories.
Pros and Cons of Radical Firearms RF Upper Assembly 8.5in 300 AAC HBAR Contour w/ A2 Flash Hider
Pros
- Reliable cycling with both supersonic and subsonic ammunition.
- Compact and maneuverable 8.5-inch barrel.
- Affordable price point, making it accessible to budget-conscious builders.
- M-LOK compatible handguard for easy accessory attachment.
- Easy to install on any MIL-STD lower receiver.
Cons
- Basic finish may not appeal to all users.
- A2 flash hider is not the most effective for muzzle flash reduction.
- Some older descriptions indicate 1:7 twist, but newer models may have 1:8, so specification needs verification prior to purchase.
Who Should Buy Radical Firearms RF Upper Assembly 8.5in 300 AAC HBAR Contour w/ A2 Flash Hider?
The Radical Firearms RF Upper Assembly 8.5in 300 AAC HBAR Contour w/ A2 Flash Hider is perfect for home defense enthusiasts, AR pistol builders, and those looking for an affordable entry into the 300 Blackout platform. It’s also a good choice for those building a truck gun or a compact SBR.
Those seeking match-grade accuracy or a premium finish might want to consider other options.
A must-have accessory would be an upgraded muzzle device, such as a suppressor or a more effective flash hider. A quality optic is also essential for maximizing the upper’s accuracy potential.
Conclusion on Radical Firearms RF Upper Assembly 8.5in 300 AAC HBAR Contour w/ A2 Flash Hider
The Radical Firearms RF Upper Assembly 8.5in 300 AAC HBAR Contour w/ A2 Flash Hider offers a compelling value proposition for those seeking a reliable and affordable 300 Blackout upper. While it may not be the most refined option on the market, it delivers consistent performance and is easy to install and maintain.
The price is definitely justified, especially considering the reliability and functionality it provides.
I would personally recommend this upper to anyone looking for a budget-friendly entry into the 300 Blackout platform or those seeking a reliable and compact upper for home defense or other tactical applications. If you are looking for a solid performing AR pistol upper without breaking the bank, this is a great option to consider.