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  • Post category:Upper Receivers
  • Post last modified:April 6, 2024
  • Post published:November 22, 2022

Best 6.8 SPC Upper Receiver Review

What is 6.8 SPC Upper Receiver? 🧐

The 6.8 Special Purpose Cartridge Upper Receiver is a key component of the 6.8 SPC calibre firearm, specifically designed for enhanced performance in a variety of tactical and hunting scenarios. It houses the barrel, bolt carrier group, charging handle, and other critical parts of the firearm. The 6.8 Special Purpose Cartridge Upper Receiver is typically lauded for its balance between power and recoil, proving to be versatile and effective in short to mid-range engagements.

Our Top Pick
Brenton USA Scout Upper Receiver
This receiver incorporates Brenton's innovative RecevierLock system, a patent-pending technology that sets a new standard for security and stability in the market. With HuntSpec controls and precise tolerances, it delivers an unparalleled hunting experience. The handguard is crafted from Brenton's cutting-edge RealFeel PolyCore material, ensuring a truly realistic tactile experience. Additionally, the charging handle is designed with a gas-diverting feature, enhancing safety during operation.
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Features 😎

The 6.8 Special Purpose Cartridge Upper Receiver boasts several notable features that make it a standout choice for firearms enthusiasts and professionals alike.

💠 Firstly, it is engineered to accommodate a larger bore, allowing it to fire 6.8 SPC caliber rounds which are known for their superior terminal ballistics- especially over .223/5.56 rounds. This potent combination of power and precision makes it a reliable option for both hunting and tactical applications.

💠 Secondly, its robust construction ensures durability under stressful conditions. The receiver is typically made from high-quality materials such as 7075-T6 aluminium, imparting resilience and longevity.

💠 Additionally, the upper receiver often comes with a Picatinny or M-LOK rail system, providing users with ample space for mounting optics, lights, and other accessories. This takes customization options to the next level, enabling users to tailor their firearm setup to their specific needs.

💠 Furthermore, many of these receivers feature a low recoil design, reducing shooter fatigue and enabling rapid follow-up shots. This makes this upper receiver an ideal choice for shooters who value a blend of power and usability.

💠 Finally, it often features a gas-operated system, which provides reliable, consistent cycling of rounds, ensuring optimal performance in the field or on the range.

Maintenance 🧼

Maintaining your upper receiver is essential to ensuring its optimal performance and longevity. Regular cleaning is a key part of this maintenance. Here are the steps to clean it effectively:

🟣 Disassemble:  Start by ensuring that your firearm is unloaded before proceeding with the disassembly. Take out the bolt carrier group and charging handle, followed by removing the handguard if it’s removable. Be sure to consult the user’s manual for specific instructions to avoid damaging any components.
🟣 Cleaning the Chamber and Bore: Use a bore brush attached to a cleaning rod to scrub the inside of the barrel. Apply a suitable gun-cleaning solvent to the brush before starting. Brush the chamber and bore thoroughly to remove any residue or dirt.
🟣 Cleaning the Bolt Carrier Group and Charging Handle:  These components often accumulate dirt and residue due to constant use. Use a small brush and cleaning solvent to clean these parts meticulously. Make sure to pay attention to small crevices and slots.
🟣 Cleaning the Upper Receiver: Use a clean cloth to wipe down the inside of the upper receiver. For stubborn debris, you may use a nylon brush. Apply solvent to areas with carbon build-up and let it sit for a few minutes before scrubbing.
🟣 Lubrication: Once all components are clean and dry, apply a high-quality firearm lubricant. Focus on the bolt carrier group, charging handle, and inside of the upper receiver. This will ensure smooth operation and prevent wear and tear.
🟣 Reassemble: After all the components are cleaned and lubricated, reassemble your firearm. Always check its functionality after reassembly to ensure that it’s operating correctly.

⭕ Remember, regular maintenance of your Upper Receiver can significantly enhance its performance and lifespan. Always follow safety guidelines when handling your firearm.

Watch this video to find more information 💻

What Are Upper Receivers Made From? 🎯

Upper receivers are typically made from materials that are selected for their ability to withstand significant wear and tear, as well as their capacity to handle the heat and pressure generated during the firing process.

⬜ One of the most common materials used in the manufacturing of upper receivers is 7075-T6 aluminium. This specific type of aluminium is a high-strength alloy, characterized by its light weight and remarkable durability. It is considered an industry standard for upper receivers because of its excellent resistance to corrosion, its ability to withstand high temperatures, and its fantastic strength-to-weight ratio. The “T6” indicates that this aluminium alloy goes through a process of heat treatment and artificial ageing to increase its hardness and durability.

⬜ Another material often used in the production of upper receivers is 6061 aluminium. While not as strong as 7075-T6, it is easier to machine and weld, and it still provides excellent durability and corrosion resistance. It is often used in the production of more economical upper receivers.

⬜ Recently, there has been a growing interest in using polymers in the construction of upper receivers. Polymer upper receivers are desirable for their lightweight and cost-effectiveness. However, while they hold up well under normal conditions, they may not offer the same level of durability and heat resistance as their aluminium counterparts.

⬜ Some high-end upper receivers are also made from steel or titanium. Steel is highly durable and can handle a large amount of heat and pressure, but it is also heavier than aluminium. Titanium, on the other hand, is lighter than steel but stronger and more heat-resistant, although it can be more expensive.

Best 6.8 SPC Upper Receiver Review

1# Radical Firearms Complete Upper Assembly

Radical Firearms Complete Upper Assembly

View on OpticsPlanet

The Radical Firearms 16in Heavy Barrel 6.8 SPC II is perfect for anyone looking for MIL-STD compliance in an upper assembly. It’s perfect for novice or experienced shooters who want to finish out a build and hit the range. The 15-inch MHR free float rail system provides increased accuracy and keeps your hands cool. And with the A2 flash hider, you’ll be ready for any situation. So whether you’re into target shooting or hunting, Radical Firearms has you covered.

Video review

  • MIL-STD compliance
  • Novice or experienced shooters
  • 15in MHR free float rail system
  • A2 flash hider
  • The rail system may be too long for some shooters


2# Brenton USA Scout Upper Receiver

Brenton USA Scout Upper Receiver

View on OpticsPlanet

Introducing the Brenton USA Scout Upper Receiver! This receiver is made with Brenton’s patent-pending RecevierLock system, making it one of the most secure and stable receivers on the market. It also features HuntSpec controls and tolerances for the ultimate hunting experience. The handguard is Brenton’s RealFeel, PolyCore material for the most realistic feel possible. The charging handle is gas-diverting for added safety. The BCG is an 8620 Carrier with a 9310 Bolt and NiB protective coating. This receiver comes with a lifetime warranty from Brenton USA against defects in materials and workmanship, as well as our Sub MOA Guarantee. We promise that your rifle will look, feel and perform like a premium hunting rifle should.

  • The Brenton USA Scout Upper Receiver is lightweight and easy to install
  • It has a durable design that can withstand wear and tear
  • The upper receiver is well-made and functions smoothly
  • The assembly process is difficult


3# Stag Arms Stag-15 6.8 SPC Super Varminter Upper Receiver

Stag Arms Stag-15 6.8 SPC Super Varminter Upper Receiver

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Whether you’re a seasoned hunter or just getting started, the Stag Arms Stag-15 6.8 SPC Super Varminter Upper Receiver is the perfect choice for game hunting. This rifle uses the powerful 6.8 SPC II cartridge for extra power, making it ideal for taking down large games. The 20.77″ barrel with an 11-degree target crown provides accuracy and precision when it counts, while the 16.5″ SL handguard and Magpul MOE pistol grip ensure a comfortable and secure grip. The Stag-15 also comes with a mil-spec Black nitride-coated M16 BCG and a Transferable Lifetime Warranty for peace of mind. So if you’re looking for a reliable and affordable rifle that will perform when it matters most, look no further than the Stag Arms Stag-15 6.8 SPC Super Varminter Upper Receiver.

Video review

  • The Stag Arms Stag-15 6.8 SPC Super Varminter Upper Receiver is a high-quality product that is built to last
  • This upper receiver is very easy to use and install
  • It offers superior accuracy and performance
  • The Stag Arms Stag-15 6.8 SPC Super Varminter Upper Receiver is a great value for the price
  • The bolt carrier group is proprietary and not interchangeable with other AR-15s
  • No forward assist or dust cover

Installation 🛠️

Installing the requires a bit of technical knowledge, but with the right tools and instructions, it can be accomplished by any firearm enthusiast. Here’s a detailed guide to help you understand the process.

🔘 Before you begin the installation process, ensure that your workspace is clean, well-lit, and free of any potential hazards. It’s also advisable to have the manufacturer’s manual on hand, as it will provide specific instructions related to your specific model.

🔘 Start by separating the upper receiver from the lower receiver of your firearm. This is typically accomplished by pushing out the takedown pins located on the lower receiver. Once the takedown pins are removed, the upper and lower receivers should separate easily.

🔘 After the receivers are separated, the next step is to remove the bolt carrier group and charging handle. To do this, pull back on the charging handle and remove the bolt carrier group. Once the bolt carrier group is removed, you can pull the charging handle all the way back and it should slide out of the receiver.

🔘 Now you are ready to install it. Insert the charging handle into the upper receiver, making sure to align the grooves on the handle with the tracks inside the receiver. Once the charging handle is in place, you can insert the bolt carrier group. Make sure the bolt is extended from the carrier and the gas key fits into the channel of the charging handle.

🔘 Finally, line up the holes on the upper receiver with the holes on the lower receiver and push the takedown pins back in. This should secure the upper receiver to the lower receiver. Once everything is securely fitted, give your firearm a quick function check to ensure everything is working correctly.

Remember, safety should always be your top priority when working with firearms. Always ensure the firearm is unloaded before starting any work on it. Following these steps should guide you through the process of installing a 6.8 Special Purpose Cartridge Upper Receiver safely and correctly.


What is the difference between 6.8 and 6.8 SPC upper receivers?

The 6.8 and 6.8 Special Purpose Cartridge upper receivers are two variations of firearm components, primarily used in AR-15-style rifles. While they share some similarities, they also have key differences that set them apart. Here, we’ll explore five key distinctions between these two upper receivers.

⬜ The primary difference between the two upper receivers lies in the cartridge they are designed to accommodate. The standard 6.8 upper receiver is designed for the 6.8mm Remington SPC cartridge, which was developed as a compromise between the 5.56mm NATO and 7.62mm NATO cartridges. On the other hand, the 6.8 Special Purpose Cartridge upper receiver is specifically tailored for the 6.8 SPC II cartridge, which is an improved version of the original 6.8 SPC.

The 6.8 Special Purpose Cartridge II cartridge offers improved ballistics and performance over the standard 6.8mm Remington SPC. It typically has better accuracy, longer effective range, and superior terminal ballistics, making it a more versatile choice for various applications, including hunting and tactical use. The 6.8 Special Purpose Cartridge II was developed to address some of the limitations of the original 6.8mm Remington SPC.

⬜ While both upper receivers can be used with AR-15 lower receivers, they are not fully interchangeable due to the differences in cartridge dimensions. A 6.8 Special Purpose Cartridge upper receiver will not reliably chamber and fire standard 6.8mm Remington SPC ammunition, and vice versa. This incompatibility extends to magazines and bolts as well.

⬜ Another crucial distinction is the availability of ammunition. The 6.8 SPC II cartridge, being an improved version, is more widely supported by ammunition manufacturers. It is easier to find a variety of factory-loaded ammunition options for the 6.8 SPC II compared to the original 6.8mm Remington SPC, which has a more limited selection.

🎯 The choice between a 6.8 and 6.8 Special Purpose Cartridge upper receiver depends on your specific use case. The 6.8 SPC II upper receiver is preferred by those looking for enhanced performance, especially in hunting or tactical applications. It offers greater versatility and better long-range capabilities.

On the other hand, the standard 6.8mm Remington SPC upper receiver may still be a suitable choice for some shooters, particularly if they have a specific preference for that cartridge or have a stockpile of 6.8mm Remington SPC ammunition.

How can I choose the best 6.8 SPC Upper Receiver?

The 6.8 Special Purpose Cartridge is a rifle cartridge designed to bridge the gap between 5.56mm and 7.62mm NATO rounds. It was developed to provide better performance than 5.56mm, especially at longer ranges, while still being usable in the AR-15 platform with minimal changes. When choosing an upper receiver for the 6.8 SPC, there are a few key factors to consider:

🔷 Barrel Length – A barrel length of 16-18 inches is common for 6.8 SPC uppers. This provides a good balance of ballistic performance and manoeuvrability. Shorter barrels will sacrifice velocity and energy on target, while longer barrels may be unwieldy.

🔷 Bolt – You’ll need a bolt designed specifically for the 6.8 SPC, as it has a larger case head diameter than 5.56mm. The bolt also needs to be hard-chromed and high-pressure tested. A quality bolt ensures reliable cycling and extraction.

🔷 Magazines – Since the 6.8 SPC case is wider, standard AR-15 magazines will not work. You’ll need specific 6.8 SPC magazines to feed the rounds properly. Look for good steel or polymer magazines from reputable brands.

🔷 Gas System – Most of these uppers use a standard carbine-length gas system, but you can also find mid-length or rifle-length gas systems. This affects the recoil and cycling rate. Consider your intended use to decide on gas system length.

🔷 Handguard – Make sure to get a handguard that will accommodate the wider 6.8 SPC cartridge. A free-float M-LOK or KeyMod handguard usually works well. This improves accuracy by isolating the barrel from external forces.

From a reputable manufacturer – Quality matters when it comes to AR components, so look for a complete upper from a trusted brand known for 6.8 SPC uppers specifically. This helps ensure optimal functioning and accuracy.

Considering these key factors will help you select a 6.8 Special Purpose Cartridge upper receiver that meets your needs and provides the ballistic performance advantages of this intermediate cartridge.

Can I use standard AR-15 magazines with a 6.8 SPC upper receiver?

Standard AR-15 magazines are typically designed for the 5.56 NATO or .223 Remington cartridges, which are smaller than the 6.8 Special Purpose Cartridge. As such, they are not ideally suited for use with a 6.8 SPC upper receiver. While you may be able to insert and feed a few 6.8 SPC rounds using a standard AR-15 magazine, the performance will likely be inconsistent, and the risk of feed failures or malfunctions will increase.

To ensure optimal performance and reliability when using a 6.8 Special Purpose Cartridge upper receiver, it is highly recommended to use magazines specifically designed for the 6.8 SPC cartridge. These magazines are constructed to accommodate the larger size and shape of the 6.8 SPC round, ensuring proper alignment and smooth feeding into the chamber of the upper receiver. By using the correct magazine, you’ll be able to experience the full potential of your 6.8 Special Purpose Cartridge upper receiver, with consistent, reliable operation.

Is the 6.8 SPC upper receiver compatible with my AR-15 lower receiver?

The compatibility largely depends on the specific models in question. However, in general terms, most AR-15 lower receivers can accept a 6.8 Special Purpose Cartridge upper receiver due to the inherent universality designed into AR-15 lower receivers. This design feature allows them to accommodate different types of upper receivers, including the 6.8 SPC variant.

To ensure a proper fit, it is always important to check with the manufacturer or consult a firearms expert who can provide guidance based on the specific components involved. They can offer valuable insight and recommendations to ensure optimal compatibility and functionality.

Additionally, it’s worth noting that while the 6.8 Special Purpose Cartridge upper receiver may fit onto the AR-15 lower receiver, using 6.8 SPC ammunition will require a corresponding 6.8 SPC magazine. This is necessary to accommodate the larger round and ensure proper feeding and reliable operation.

What are the types of 6.8 SPC Upper Receivers?

They come in a variety of types, each designed to cater to different needs and preferences of firearm enthusiasts. Some of the notable types include:

  1. 🟨 Standard Upper Receivers: These are the most common type of upper receivers. They typically include a forward assist and a dust cover. They are designed to comply with the military specifications (Mil-Spec) and are usually made from 7075-T6 aluminium, delivering a solid performance under a wide range of conditions.
  2. 🟨 Flat Top Upper Receivers: These types of receivers are characterized by their flat upper surface, devoid of any carry handle. This design provides a long, uninterrupted rail space for the attachment of various optical devices, making them a preferred choice for shooters who require custom optics for hunting or target shooting.
  3. 🟨 Billet Upper Receivers: Billet upper receivers are made from a single block of material, usually 6061 or 7075-T6 aluminium. They are CNC-machined to precise dimensions, providing a higher degree of customization in terms of aesthetic and functional features.
  4. 🟨 Lightweight Upper Receivers: As the name suggests, these receivers are designed to reduce the overall weight of the firearm without compromising on strength or durability. They often incorporate larger cutouts and thinner walls and may be made from lightweight materials like polymer or certain aluminium alloys.
  5. 🟨 Monolithic Upper Receivers: These upper receivers feature a one-piece design where the receiver and the handguard are made from a single piece of material. This design promotes greater consistency and accuracy by providing a rigid platform that reduces the impact of external forces on the barrel.

Each type, while differing in design and features, delivers the same end goal – to provide firearm enthusiasts with a reliable, high-performing component that elevates their shooting experience. The choice of the type of upper receiver generally depends on the individual user’s needs, preferences and budget.

What finish can be on 6.8 SPC Upper Receivers?

They can be finished in several ways, enhancing their appearance and providing additional protection against wear and tear. The most common finish is the anodized finish, notably the Type III anodizing, also known as hard coat anodizing. This finish, which involves the application of a protective oxide layer, enhances the receiver’s durability and increases its resistance to corrosion.

Another popular finish option is Cerakote, a polymer-ceramic coating renowned for its excellent protection against abrasion, corrosion, and UV rays. Not only does it provide exceptional durability, but it also offers a wide range of colour possibilities for customization, allowing users to create a unique and personalized look for their upper receivers.

For those seeking enhanced hardness, wear resistance, and lubricity, the Nitride finish is a great choice. Through the diffusion of nitrogen into the surface of the receiver, it forms a hard and durable layer that significantly improves its performance and longevity.

Lastly, some upper receivers feature a Nickel Boron finish, known for its low friction and high hardness properties. This finish not only enhances the overall performance but also contributes to the receiver’s long-lasting durability.

Each finish option has its unique advantages, allowing users to select the one that best suits their specific needs and preferences. Whether it’s maximizing durability, customizing appearance, or optimizing performance, the choice of finish plays a crucial role in the overall functionality and aesthetics of Upper Receivers.

Conclusion 🤩

The 6.8 SPC Upper Receiver, with its admirable durability and versatility, is a top choice for firearm enthusiasts seeking a high-performing, reliable component. Its design, which emphasizes low recoil, aids in reducing shooter fatigue, making it suitable for prolonged use.

With customizable rail systems such as Picatinny or M-LOK, users can personalize their set-up to meet individual needs. The receiver’s material, usually a robust alloy like 7075-T6 or 6061 aluminium, guarantees longevity even under challenging conditions.

Furthermore, the installation process, while requiring attention to detail, can be accomplished by anyone with a keen interest in firearms and basic technical knowledge.

Overall, these Upper Receiver is a testament to the blend of engineering and craftsmanship in the realm of firearms.

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Willie Karlton
Willie Karlton
6 months ago

My 6.8 SPC upper seems to have ejection issues. It occasionally fails to eject spent casings properly, causing jams. Is there a common fix for this, or should I start troubleshooting?

    6 months ago
    Reply to  Willie Karlton

    Ejection issues can be related to several factors, including the extractor, ejector, and gas system. First, clean and inspect your bolt assembly, extractor, and ejector for any wear or damage. Ensure your gas system is properly tuned for the 6.8 SPC. If problems persist, consider consulting with a gunsmith.

      6 months ago

      I switched to a 6.8 SPC upper last deer season, and I’ve had great success with it. Took down a nice buck at 150 yards with one shot.

        6 months ago

        I’ve been running a 6.8 SPC upper on my AR for a while now, and I love it. It’s got better terminal ballistics than the 5.56 and still has manageable recoil.

          6 months ago

          I’ve been having some issues with my 6.8 SPC upper, particularly with feeding. It seems to jam more frequently than my 5.56 setup. Anyone else experienced this? Any advice on how to fix it?

            6 months ago
            Reply to  Randy

            I had similar feeding issues initially with my 6.8 SPC upper. What helped me was switching to higher-quality magazines, specifically designed for the 6.8 SPC. It made a significant difference in reliability.

              6 months ago

              Hello! Are there different barrel lengths available for 6.8 SPC upper receivers?