Complete AR15 Upper Receiver Guide: Aero, Geissele, Faxon & WTS Options
Are you looking to build or upgrade your AR-15? The AR15 upper receiver is a critical component, and choosing the right one can significantly impact your rifle's performance, accuracy, and reliability. This comprehensive guide will walk you through the key aspects of a complete AR-15 upper, focusing on quality brands like Aero Precision, Geissele, and Faxon, and what to look for when considering a WTS (willing to sell) option. We'll delve into the components that make up a complete upper, the advantages of each brand, and the factors to consider when purchasing a used upper. Whether you're a seasoned AR-15 enthusiast or a first-time builder, this article will provide the knowledge you need to make an informed decision.
Understanding the AR15 Upper Receiver
The AR15 upper receiver is the assembly that houses the bolt carrier group, barrel, and gas system. It's the heart of your AR-15's functionality, directly influencing accuracy, recoil management, and overall performance. A complete upper includes the upper receiver itself, the bolt carrier group (BCG), the barrel, the handguard, the gas system (gas block and gas tube), and the muzzle device. Choosing high-quality components for your upper is essential for a reliable and accurate AR-15.
Key Components of a Complete AR15 Upper:
- Upper Receiver: This is the main housing for the internal components. It's typically made from forged or billet aluminum and should be durable and precisely machined. Look for 7075-T6 aluminum for maximum strength and longevity.
- Bolt Carrier Group (BCG): The BCG is responsible for cycling the action of the rifle, extracting spent casings, and chambering new rounds. A high-quality BCG is crucial for reliability. Common materials include Carpenter 158 steel and 9310 steel. Consider a BCG with a Magnetic Particle Inspection (MPI) and High Pressure Testing (HPT) certification for added assurance.
- Barrel: The barrel is the component that dictates the bullet's trajectory and contributes significantly to accuracy. Factors to consider include barrel length, twist rate, material (4150 Chrome Moly Vanadium or 416R Stainless Steel), and finish (nitride or chrome lining). The appropriate barrel length depends on your intended use, with 16-inch barrels being a popular all-around choice. Twist rate refers to the rate at which the rifling inside the barrel rotates the bullet, and a 1:7 or 1:8 twist rate is suitable for most common bullet weights.
- Handguard: The handguard protects the barrel, provides a mounting platform for accessories, and allows for a comfortable grip. Popular options include free-floating handguards, which do not contact the barrel, improving accuracy. Handguards are often made from aluminum or carbon fiber and come in various lengths and styles, such as M-LOK or KeyMod.
- Gas System: The gas system uses gas from the fired cartridge to cycle the action. It consists of a gas block and a gas tube. Gas systems come in different lengths (pistol, carbine, mid-length, and rifle), with mid-length systems often preferred for 16-inch barrels due to their smoother recoil impulse.
- Muzzle Device: The muzzle device is attached to the end of the barrel and can serve various purposes, such as reducing recoil (muzzle brake), minimizing muzzle flash (flash hider), or suppressing sound (suppressor). Common muzzle devices include A2 flash hiders, compensators, and muzzle brakes.
Aero Precision: Quality and Affordability
Aero Precision is a well-respected manufacturer known for producing high-quality AR-15 components at competitive prices. Their uppers are a popular choice for both budget-conscious builders and experienced enthusiasts. Aero Precision uppers are typically made from 7075-T6 aluminum forgings, ensuring durability and reliability. They offer a variety of upper receiver options, including stripped uppers, assembled uppers, and complete uppers. Aero Precision's commitment to precision machining and quality control makes them a reliable choice for your AR-15 build.
Key Features of Aero Precision Uppers:
- 7075-T6 Aluminum Forgings: This high-strength aluminum alloy ensures the upper receiver can withstand the stresses of repeated firing.
- Precise Machining: Aero Precision's stringent manufacturing processes result in uppers with tight tolerances and consistent dimensions.
- M4 Feed Ramps: M4 feed ramps improve feeding reliability, especially with a wide range of ammunition.
- Variety of Options: Aero Precision offers a wide selection of uppers, allowing you to customize your build to your specific needs.
- Affordable Price Point: Aero Precision provides excellent value for the money, making their uppers accessible to a broad range of builders.
When considering an Aero Precision complete upper, you can expect a well-made product that will provide reliable performance. Their uppers are a solid foundation for any AR-15 build, whether you're building a budget-friendly plinker or a more serious defensive rifle.
Geissele Automatics: Premium Performance and Reliability
Geissele Automatics is a premium manufacturer renowned for producing high-end AR-15 components, including uppers, triggers, and rails. Geissele uppers are known for their exceptional quality, precision, and reliability. They are a favorite among competitive shooters, law enforcement professionals, and anyone who demands the best possible performance from their AR-15.
Key Features of Geissele Uppers:
- Superior Materials and Manufacturing: Geissele uppers are often made from high-grade materials and undergo rigorous quality control processes.
- Enhanced Accuracy: Geissele uppers are designed for maximum accuracy, with tight tolerances and precise machining.
- Proprietary Designs: Geissele incorporates proprietary designs and features into their uppers, such as their Super Duty Upper Receiver, which enhances strength and rigidity.
- Exceptional Reliability: Geissele components are known for their reliability, ensuring your AR-15 will function flawlessly in demanding conditions.
- Premium Price Point: Geissele uppers command a higher price than other options, but their performance and quality justify the investment for serious shooters.
If you're looking for the ultimate in AR15 upper performance and reliability, a Geissele complete upper is an excellent choice. Their attention to detail and commitment to quality make their uppers a top-tier option for any AR-15 build.
Faxon Firearms: Innovation and Quality Barrels
Faxon Firearms is a manufacturer specializing in innovative AR-15 barrels and other components. They are known for their high-quality barrels, which are often a key component in their complete uppers. Faxon barrels are available in various lengths, profiles, and materials, allowing you to tailor your AR-15's performance to your specific needs.
Key Features of Faxon Uppers:
- High-Quality Barrels: Faxon's barrels are known for their accuracy, durability, and innovative designs. They offer a wide range of barrel options, including fluted barrels, lightweight barrels, and barrels with different twist rates.
- Nitride Finish: Faxon barrels typically feature a nitride finish, which enhances corrosion resistance and extends barrel life.
- Variety of Options: Faxon offers complete uppers in various configurations, allowing you to choose the barrel length, handguard, and other features that best suit your needs.
- Competitive Price Point: Faxon uppers offer a good balance of quality and affordability, making them a popular choice for many AR-15 builders.
- Lightweight Options: Faxon is known for its lightweight barrels and uppers, which can reduce the overall weight of your AR-15, making it easier to carry and maneuver.
When considering a Faxon complete upper, you can expect a high-quality barrel that will contribute to excellent accuracy and performance. Their uppers are a great option for those looking for a reliable and accurate AR-15 build.
WTS (Willing to Sell) Considerations: Buying Used Uppers
When considering a WTS (willing to sell) AR15 upper, there are several factors to keep in mind. Buying a used upper can be a cost-effective way to acquire quality components, but it's essential to inspect the upper carefully before making a purchase. Here are some key considerations:
Key Considerations When Buying a Used Upper:
- Condition: Examine the upper for signs of wear and tear, such as scratches, dents, or corrosion. Pay close attention to the barrel, BCG, and other critical components. If possible, ask for detailed photos or inspect the upper in person.
- Round Count: Inquire about the round count of the upper. A high round count may indicate significant wear on the barrel and BCG. While AR-15s are durable, components will eventually wear out over time.
- Brand and Quality: Research the brand and model of the upper. Reputable brands like Aero Precision, Geissele, and Faxon are generally a safer bet than unknown or low-quality brands.
- Compatibility: Ensure the upper is compatible with your lower receiver. AR-15 uppers and lowers are generally standardized, but it's always best to verify compatibility before making a purchase.
- Price: Compare the price of the used upper to the price of a new upper. A significant discount may be justified for a used upper, but be wary of deals that seem too good to be true.
- Seller Reputation: If purchasing online, check the seller's reputation and feedback. Buy from reputable sellers with positive reviews to minimize the risk of scams or misrepresentation.
- Inspection: If possible, inspect the upper in person before making a purchase. Check the barrel rifling, the bolt carrier group's condition, and the overall fit and finish of the upper.
Buying a used AR15 upper receiver can be a viable option, but it requires careful consideration and inspection. By following these guidelines, you can increase your chances of acquiring a quality upper at a fair price.
Assembling Your Complete AR15 Upper
Once you've chosen your components, you'll need to assemble your complete AR15 upper. While some individuals prefer to purchase a pre-assembled upper, assembling your own allows for greater customization and a deeper understanding of your rifle's mechanics. If you're not comfortable assembling your own upper, you can always seek the assistance of a qualified gunsmith.
Tools and Equipment:
- Upper Receiver Vise Block: This tool holds the upper receiver securely in a vise during assembly.
- Torque Wrench: A torque wrench is essential for properly tightening the barrel nut and other components to the manufacturer's specifications.
- AR-15 Armorer's Wrench: This wrench is used to tighten and loosen the barrel nut, castle nut, and other components.
- Roll Pin Punches: Roll pin punches are used to install and remove roll pins, which secure various components.
- Hammer: A hammer is used in conjunction with roll pin punches to install roll pins.
- Grease or Anti-Seize Compound: Grease or anti-seize compound is applied to the barrel nut threads to ensure proper tightening and prevent seizing.
- Headspace Gauges: Headspace gauges are used to verify the headspace of the rifle, which is the distance between the bolt face and the shoulder of the chamber. Proper headspace is crucial for safety and reliability.
Assembly Steps:
- Install the Barrel: Apply grease or anti-seize compound to the barrel extension threads. Insert the barrel into the upper receiver and install the barrel nut. Tighten the barrel nut to the manufacturer's specified torque using a torque wrench.
- Install the Gas Block: Slide the gas block over the barrel and align it with the gas port. Secure the gas block using the appropriate hardware.
- Install the Gas Tube: Insert the gas tube into the gas block and secure it with a roll pin.
- Install the Handguard: Slide the handguard over the barrel and secure it to the barrel nut or upper receiver, depending on the design.
- Install the Muzzle Device: Screw the muzzle device onto the barrel and tighten it using the appropriate wrench.
- Install the Forward Assist and Ejection Port Cover: Install the forward assist and ejection port cover using roll pins.
- Install the Bolt Carrier Group: Insert the bolt carrier group into the upper receiver.
- Check Headspace: Use headspace gauges to verify the headspace of the rifle. If the headspace is not within the specified range, the rifle is unsafe to fire.
Assembling your own complete AR15 upper assembly can be a rewarding experience, but it's essential to follow the proper procedures and use the correct tools. If you're not comfortable with any of these steps, seek the assistance of a qualified gunsmith.
Conclusion: Choosing the Right Complete AR15 Upper
Selecting the right AR15 complete upper is a crucial step in building or upgrading your AR-15. Consider your budget, intended use, and desired level of performance when making your decision. Brands like Aero Precision, Geissele, and Faxon offer a range of options to suit various needs and preferences. Whether you prioritize affordability, premium performance, or innovative features, there's a complete upper that's right for you. Remember to carefully consider the components included in the upper, the reputation of the manufacturer, and any potential risks when buying used. With the knowledge gained from this guide, you're well-equipped to make an informed decision and build an AR-15 that meets your exact specifications and delivers the performance you expect.