AERO PRECISION APAR505611 AR15 20" UPPER PINNED FSB & A2 HANDGUARD

The Aero Precision AR-15 20" Complete Upper Receiver with Pinned FSB and A2 Handguard

stands as a cornerstone for builders and enthusiasts aiming for a classic, high-performance rifle. This complete upper assembly provides a robust and reliable foundation, perfect for replicating the iconic M16A4 service rifle or for those who simply appreciate the enduring design and functionality of a fixed front sight and detachable carry handle system. Crafted with precision and attention to detail, this unit embodies the quality and heritage that define American-made firearms components.

For anyone asking, "What's the best way to start an AR-15 rifle build with traditional aesthetics?" or "Where can I find a durable, ready-to-install upper that respects Mil-Spec standards?", this Aero Precision offering is an exceptional answer. It eliminates the complexities of assembling an upper from individual components, providing a factory-integrated solution that ensures optimal alignment and performance right out of the box. Whether you're a seasoned gunsmith, a first-time builder, or a shooter looking to upgrade an existing lower receiver, this upper delivers a professional-grade solution designed for longevity and accuracy.

Unpacking the Core Components: A Deep Dive into Performance and Durability

The heart of any AR-15 is its upper receiver and barrel, and Aero Precision has engineered this unit to exceed expectations. The Standard M4 Upper Receiver serves as the robust chassis, providing a solid platform for all other components. Manufactured to precise Mil-Spec dimensions, it ensures seamless compatibility with any standard AR-15 lower receiver, making your build process straightforward and reliable. The anodized black finish not only provides a sleek, uniform appearance but also offers enhanced corrosion resistance and durability, protecting your investment from the elements and the rigors of regular use.

Central to this upper's capability is its 20-inch 5.56 NATO barrel. This length is historically significant, mirroring the rifle-length gas system used in military service rifles, which contributes to smoother cycling, reduced recoil, and improved long-range accuracy compared to shorter carbine setups. The barrel is constructed from 4150 Chrome Moly Vanadium steel, a material renowned for its high strength, wear resistance, and ability to withstand the extreme pressures and temperatures of firing. This specific alloy ensures your barrel maintains its integrity and accuracy shot after shot, extending its service life significantly.

Further enhancing the barrel's longevity and performance is the QPQ (Quench Polish Quench) corrosion-resistant finish. Also known as salt bath nitride, this advanced treatment creates an extremely hard, slick, and corrosion-resistant surface both inside and outside the barrel. What does this mean for the shooter? It translates to less friction for projectiles, easier cleaning, and superior protection against rust and wear, even in harsh environments. This is a critical feature for anyone demanding peak performance and minimal maintenance from their firearm.

The barrel features a 1:7 twist rate, which is optimized for stabilizing a wide range of 5.56 NATO and .223 Remington bullet weights, including heavier, longer projectiles commonly used for precision shooting and duty applications. This versatility ensures excellent accuracy whether you're shooting standard 55-grain M193 ammunition or heavier 77-grain OTM rounds. The rifle-length gas system further complements the 20-inch barrel, allowing for a longer dwell time and lower operating pressures, which results in a softer recoil impulse and reduced wear on internal components. This makes for a more pleasant shooting experience and contributes to the overall reliability of the system.

Classic Sighting and Ergonomics: The Pinned FSB and A2 Carry Handle

A defining characteristic of this Aero Precision upper is its classic sighting system. It includes a Pinned Front Sight Block (FSB) with Bayonet Lug and an A2 Detachable Carry Handle. For those wondering, "Why choose a fixed front sight in an era of optics?" The answer lies in unwavering reliability. A pinned FSB is incredibly robust and virtually indestructible, offering a sight picture that will never lose zero due to impacts or extreme temperatures. It serves as an excellent primary sighting system or as an absolutely dependable backup for any optic you choose to mount. The integrated bayonet lug, while a nod to military heritage, also adds to the authentic M16A4 aesthetic.

The A2 Detachable Carry Handle is a versatile component that brings multiple benefits. Beyond its ergonomic purpose for carrying the rifle, it incorporates a fully adjustable rear sight, allowing for precise windage and elevation adjustments. This provides a reliable and accurate iron sight solution straight out of the box. Furthermore, the Picatinny rail section underneath the carry handle allows for the easy attachment of red dot sights or other optics, offering flexibility for modern shooting preferences while retaining the ability to quickly revert to iron sights. This dual functionality is incredibly valuable for shooters who appreciate both traditional methods and contemporary upgrades.

A2 Style Handguard: Enduring Functionality and Form

The A2 Style Handguard, Rifle Length, completes the classic look and feel of this upper. These two-piece polymer handguards are lightweight, durable, and offer excellent heat dissipation, protecting your hand during extended firing sessions. For many, the A2 handguard represents the quintessential AR-15 aesthetic, embodying simplicity and effective functionality. While modern rail systems offer more attachment points, the A2 handguard is perfect for builds prioritizing authenticity, weight savings, and a clean profile. Its robust design is well-suited for a wide range of applications, from range training to field use.

American Craftsmanship: The Aero Precision Advantage

"Why choose Aero Precision for your AR-15 build?" is a question often asked by new and experienced builders alike. The answer lies in their unwavering commitment to quality and their "Made In America" philosophy. Aero Precision is renowned for producing high-quality, Mil-Spec components that are manufactured entirely in the United States. This commitment ensures strict quality control, superior material sourcing, and adherence to the highest manufacturing standards. When you invest in an Aero Precision product, you're not just buying a part; you're investing in American ingenuity and craftsmanship that translates directly into reliable performance and exceptional durability. Their reputation for precision engineering and rigorous testing means that every component, including this complete upper, is built to perform flawlessly.

This dedication to quality is evident in the specific attributes of this upper. The precise machining of the upper receiver, the careful pinning of the FSB, and the robust finish all speak to a product designed to last for generations. Choosing Aero Precision means choosing a brand trusted by competitive shooters, law enforcement, and military personnel for their demanding applications.

Who is this Aero Precision Upper for? Real-World Applications.

• M16A4 Clone Builders: This upper is the exact same one used in the AERO M16A4 Special Edition Complete Rifle, making it the perfect choice for historical accuracy and authenticity. If your goal is to recreate a service rifle, look no further.
• Long-Range Precision Shooters: The 20-inch barrel with a 1:7 twist and rifle-length gas system offers excellent ballistic performance and a smoother shooting experience, ideal for hitting targets at extended distances.
• Hunters: With its robust construction and reliable performance, this upper is well-suited for varmint hunting or medium-game hunting where the 5.56 NATO round is appropriate.
• Competitive Shooters: While often associated with modern rail systems, the reliability of a fixed front sight and the balance of a 20-inch barrel can be advantageous in certain competition formats.
• Home Defense Enthusiasts: A reliable and accurate AR-15 is a top choice for home defense, and this complete upper provides a dependable foundation.
• General Purpose Rifle Builders: If you desire a versatile AR-15 that balances traditional aesthetics with modern performance, this upper offers an excellent starting point.
• Enthusiasts seeking a "Buy Once, Cry Once" solution: The quality and durability of this Aero Precision upper mean it's an investment that will continue to perform reliably for years to come.

Building Your Dream Rifle: What Else Do You Need?

This complete upper assembly is designed to streamline your build process. It includes the upper receiver, barrel, pinned front sight block, A2 handguard, detachable carry handle, gas tube, and A2 flash hider. As indicated, this complete upper does not include a Bolt Carrier Group (BCG) or Charging Handle. These essential components are necessary to make your rifle operational and are typically purchased separately to allow for user preference in materials and design. Fortunately, reputable retailers like DEGuns offer a wide selection of high-quality BCGs and charging handles that will perfectly complement your Aero Precision upper. Integrating these components is a straightforward process, allowing you to quickly finish your custom rifle build.

Optimized for Performance and Longevity

The rigorous manufacturing processes and material selection for this Aero Precision upper ensure it stands up to demanding use. The QPQ nitride finish on the barrel significantly reduces wear and tear, extending the barrel's life far beyond that of standard phosphated or chrome-lined barrels. The precision fit of the pinned front sight block ensures that your iron sights maintain their zero without shift. The Mil-Spec adherence throughout the design means that parts interchangeability and future upgrades are simplified. This upper is not just a collection of parts; it is an integrated system designed for optimal function and enduring reliability, providing peace of mind to the end-user.

In summary, for those seeking to assemble a high-quality, reliable, and aesthetically classic AR-15 rifle, the Aero Precision 20" Complete Upper with Pinned FSB and A2 Handguard is an outstanding choice. Its combination of premium materials, Mil-Spec construction, and thoughtful design makes it a top-tier option for a wide array of shooting disciplines and building projects. Discover the full range of Aero Precision components and all the accessories you need to finish your build at DEGuns, your trusted online source for firearms and parts.

Technical Specifications: Aero Precision AR-15 20" Upper (UPC: 815421029272)