Aero Precision M4E1 Threaded Complete Upper, 16" .300 Blackout Barrel, 12" M-LOK ATLAS S-ONE Handguard - Anodized Black

Optimize Your AR-15 Build: The Aero Precision M4E1 Threaded 16" .300 Blackout Complete Upper with ATLAS S-ONE Handguard

Are you an AR-15 enthusiast looking to significantly upgrade your firearm's performance, reduce its overall weight, and enhance its aesthetics? Perhaps you're embarking on a new build and searching for a top-tier, ready-to-install upper receiver that delivers precision, reliability, and modern features right out of the box. Or maybe you're a hunter seeking a compact, potent rifle for medium game, or a sport shooter aiming for improved maneuverability and handling. For all these scenarios, the Aero Precision M4E1 Threaded Complete Upper Receiver, featuring a 16-inch .300 Blackout CMV Barrel and the innovative ATLAS S-ONE Handguard, stands out as an exceptional choice. This complete upper, available at DEGuns, embodies the perfect fusion of cutting-edge design, robust engineering, and practical functionality, making it an ideal foundation for your next high-performance AR-15.

What Makes This Complete Upper a Game-Changer for Your AR-15?

This meticulously assembled complete upper solves numerous challenges for builders and shooters alike. It eliminates the complexities and potential compatibility issues often encountered when sourcing individual components, ensuring a seamless and reliable fit from day one. Designed for those who prioritize a lightweight rifle without compromising on strength or stability, it's particularly suited for applications where agility and reduced fatigue are paramount, such as extended range sessions, tactical drills, or long days in the field.

Key advantages of opting for this complete upper include:

• Simplified Assembly: No need to source a separate upper receiver, handguard, barrel, gas block, or gas tube. This unit comes fully assembled, saving you time, effort, and specialized tools.
• Guaranteed Compatibility: All components are designed and manufactured by Aero Precision to work together flawlessly, ensuring optimal performance and cycling reliability.
• Weight Reduction: The ATLAS S-ONE handguard is engineered for minimal mass, contributing significantly to a lighter overall rifle, which translates to improved handling and less fatigue during prolonged use.
• Enhanced Ergonomics: The slim profile of the handguard and integrated indexing grooves provide superior grip control and a comfortable shooting experience.
• Versatile Caliber: The .300 Blackout chambering offers exceptional versatility, performing effectively with both supersonic and subsonic ammunition, making it adaptable for diverse shooting scenarios.

Deep Dive into the M4E1 Threaded Upper Receiver

The foundation of this impressive assembly is the M4E1 Threaded Assembled Upper Receiver, a testament to Aero Precision's commitment to innovation and quality. Unlike traditional forged uppers, the M4E1 boasts a new enhanced forging process that gives it a distinct "billet look" – an aesthetic appeal often associated with more expensive, machined receivers. This isn't just about looks; the advanced forging contributes to increased structural integrity.

Key Features of the M4E1 Threaded Upper Receiver:

• "Billet Look" Forging: Provides a premium, high-end appearance without the premium price tag, seamlessly integrating with modern AR-15 lower receivers.
• Enhanced Picatinny Profile: The top rail is redesigned to blend seamlessly with Aero Precision's Enhanced Series Handguards, creating a monolithic aesthetic when paired with compatible handguards like the ATLAS S-ONE. This seamless transition also provides a continuous mounting surface for optics and accessories.
• M4 Feedramps: Essential for reliable feeding of ammunition, particularly with the diverse projectile types common in .300 Blackout, ensuring smooth cycling and minimizing malfunctions.
• .250 Takedown Pin Holes: Adheres to mil-spec standards, ensuring compatibility with a wide range of AR-15 lower receivers.
• Laser Engraved T-marks: These tactical markings on the picatinny rail allow for precise and repeatable placement of optics and other accessories, critical for maintaining zero and consistency.
• Installed Port Door and Forward Assist: Ready for immediate use, these components are pre-installed, eliminating the need for additional parts or specialized tools during your build process. The forward assist provides a mechanical means to ensure the bolt is fully seated, a crucial reliability feature.

Unpacking the ATLAS S-ONE Handguard: Lightweight, Strong, and Sleek

One of the standout features of this complete upper is the included ATLAS S-ONE Handguard. Designed with meticulous attention to detail, its primary goal is to provide a lightweight yet incredibly robust platform for your accessories and a comfortable grip. The proprietary ATLAS (Aero Taper Lock Attachment System) is a revolutionary mounting solution that ensures a rock-solid lockup without the bulk of traditional mounting systems.

Benefits and Features of the ATLAS S-ONE Handguard:

• Designed for Size and Weight: At just 1.3 inches inside diameter and 1.5 inches outside diameter, the ATLAS S-ONE offers an incredibly slim profile. This slender design not only feels great in hand but also significantly reduces the overall weight of the upper, enhancing maneuverability and reducing shooter fatigue.
• Proprietary ATLAS Attachment System: This innovative mounting system is engineered for durability and dependable performance. It maintains an ultra-slim profile while delivering the strength and stability that Aero Precision handguards are renowned for. The unique attachment method minimizes bulk, ensuring a secure fit that stands up to rigorous use.
• Front and Rear Picatinny Rail: While optimizing for weight, the handguard retains essential picatinny rail sections at the 12 o'clock position at both the front and rear, providing crucial mounting points for front sights, optics, and other rail-mounted accessories.
• Eliminated Center of Top Rail: By removing the center section of the top picatinny rail, Aero Precision achieves significant weight reduction without sacrificing functionality for most users who run optics that bridge the receiver and handguard.
• Indexing Grooves in 12:00 Position: These strategically placed grooves offer a positive, non-slip grip, enhancing weapon control, especially in adverse conditions or during rapid fire.
• Quick Disconnect (QD) Sling Sockets: Integrated at the 3, 6, and 9 o'clock positions, these sockets provide versatile and rapid attachment points for QD slings, allowing for easy transitions between carry methods and enhanced rifle retention.
• Low Profile Gas Block Compatibility: The handguard's design ensures seamless compatibility with most low-profile gas blocks, which is essential for proper gas system function and a clean aesthetic under the rail.
• Mil-Spec AR15 Compatibility: This handguard is designed to be compatible with standard mil-spec AR15 upper receivers and barrels, ensuring broad compatibility for various builds.

The Power of .300 Blackout: 16" CMV Barrel Performance

At the heart of this complete upper lies the 16-inch .300 Blackout barrel, a versatile and increasingly popular caliber known for its effectiveness in various roles. This barrel is crafted from 4150 Chrome Moly Vanadium (CMV) steel, a material widely recognized in the firearms industry for its excellent strength, wear resistance, and ability to handle high pressures.

Barrel Specifications and Performance Benefits:

• Chamber: .300 Blackout: The .300 Blackout caliber offers unique advantages, particularly for those interested in suppressed shooting or hunting at moderate ranges. It can effectively cycle both heavy, subsonic rounds (often used with suppressors for quiet operation) and lighter, supersonic rounds (for increased velocity and flatter trajectories). This versatility makes it ideal for everything from home defense to hog hunting.
• Length: 16 Inches: This barrel length strikes an excellent balance, providing sufficient velocity for supersonic rounds while still being compact enough for maneuverability. Importantly, a 16-inch barrel avoids the need for NFA paperwork typically associated with Short Barreled Rifles (SBRs), offering a straightforward and legal build for most users.
• Material: 4150 Chrome Moly Vanadium: This steel alloy provides a strong and durable barrel, capable of withstanding the rigors of high-volume shooting and maintaining accuracy over its lifespan.
• Finish: QPQ Corrosion Resistant Finish: The Quench Polish Quench (QPQ) finish is a type of nitrocarburizing that enhances the barrel's surface hardness, corrosion resistance, and lubricity. This means easier cleaning, less wear, and superior protection against rust and environmental elements, extending the barrel's life and ensuring consistent performance.
• Gas System Length: Pistol: For the .300 Blackout caliber, a pistol-length gas system is generally optimized for reliable cycling across a wide range of ammunition, especially when using subsonic rounds and suppressors. It ensures proper gas pressure for the bolt carrier group to cycle efficiently.
• Gas Block Journal: .750 Inches: This standard diameter ensures compatibility with a vast array of aftermarket gas blocks, though a low-profile gas block is already included.
• Twist Rate: 1:7 Inches: This aggressive twist rate is crucial for stabilizing heavier .300 Blackout projectiles (typically 190 grains and above), which are commonly used for subsonic and suppressed applications, ensuring optimal accuracy and ballistic performance.
• Muzzle: 5/8x24 Threaded: The industry-standard threading allows for easy attachment of a wide variety of muzzle devices, including flash hiders, compensators, and most importantly, suppressors.
• Weight: 29 oz (Barrel Only): This is a reasonable weight for a 16-inch CMV barrel, contributing to the overall lightweight philosophy of this complete upper.
• M4 Feed Ramp Extension: Provides extended feed ramps from the barrel extension into the upper receiver, enhancing feeding reliability, especially with different bullet profiles.
• HP and MPI Tested: The barrel undergoes High Pressure (HP) testing and Magnetic Particle Inspection (MPI). HP testing fires an over-pressure round to ensure the barrel can withstand extreme stress, while MPI detects any microscopic flaws or cracks that could compromise safety or performance. These tests signify a commitment to quality and safety.
• Standard A2 Flash Hider: Included and pre-installed, this classic muzzle device effectively reduces muzzle flash, preserving the shooter's night vision and reducing their signature.

Ready for Your Custom Build – What's Included and What's Not?

This complete upper comes fully assembled, offering unparalleled convenience for builders. This means the M4E1 Threaded Assembled Upper Receiver, the Enhanced Handguard (ATLAS S-ONE), the 16-inch .300 Blackout CMV Barrel, and the Low Profile Gas Block and Pistol Length Gas Tube are all expertly put together. You can skip the specialized tools and the potential headaches of assembling these critical components yourself.

Please note: This complete upper does not include a Bolt Carrier Group (BCG) or a Charging Handle. This is a deliberate choice that offers significant benefits to the end-user:

• Customization Freedom: It allows you to select a BCG and charging handle that best suits your specific needs, budget, and performance preferences. Do you prefer a standard mil-spec BCG, a lightweight version, or one with a specialized coating? Do you need an ambidextrous charging handle or a specific design for suppressed shooting? This flexibility ensures your rifle is truly optimized for you.
• Cost Efficiency: You only pay for the components you need, avoiding redundant parts if you already own a high-quality BCG and charging handle from a previous build or upgrade.

Who Will Benefit Most from This Aero Precision Upper?

• First-Time AR-15 Builders: Get a significant head start on your build with a high-quality, pre-assembled core component.
• Experienced Enthusiasts: Looking to create a lightweight, high-performance .300 Blackout rifle for specific applications like hog hunting, suppressed shooting, or home defense.
• Hunters: The .300 Blackout's ballistic properties and the upper's lightweight design make it excellent for short to medium-range hunting of various game.
• Competitive Shooters: The ergonomic ATLAS S-ONE handguard and balanced 16-inch barrel contribute to rapid target acquisition and improved control.
• Anyone Seeking Reliability: Aero Precision's rigorous testing and manufacturing standards ensure this upper is built to last and perform consistently.

By choosing the Aero Precision M4E1 Threaded Complete Upper with a 16" .300 Blackout CMV Barrel and ATLAS S-ONE Handguard, you are investing in a proven, high-quality component that will serve as the backbone of an exceptional AR-15 rifle. Its thoughtful design, superior materials, and precision assembly reflect Aero Precision's reputation as a leading manufacturer in the firearms industry, ensuring you receive a product that is both durable and dependable.

This premium complete upper is available at DEGuns, your trusted source for top-tier firearm components. Upgrade your AR-15 with confidence and experience the difference that genuine quality makes.

Product Specifications