Building your own AR-10 from an 80% lower receiver can be a rewarding experience, offering a level of customization and cost savings unavailable with pre-built rifles. However, it's crucial to understand the legal implications and the process involved before you begin. This guide provides a comprehensive overview of AR-10 80% lower receivers, covering everything from legality to the build process itself.
What is an 80% Lower Receiver?
An 80% lower receiver is an unfinished firearm receiver that lacks the critical features necessary to be classified as a functional firearm under the Gun Control Act of 1968 (GCA). These missing features—typically the fire control group pocket, trigger pin holes, and hammer pin holes—require machining or other modifications to complete. Because they are not yet firearms, they are generally not subject to the same regulations as complete firearms. This means they are often easier to acquire than complete lower receivers. The AR-10 variant is simply the larger-caliber version of the popular AR-15 platform.
Legality of 80% Lower Receivers
The legality of 80% lower receivers varies significantly depending on your location. Always check your local, state, and federal laws before purchasing or working with an 80% lower receiver. Some jurisdictions may have strict regulations or outright bans on the possession or manufacturing of these components. Failure to comply with these laws can result in serious legal consequences. This information is for educational purposes only and should not be considered legal advice. Consult with legal counsel to ensure you are complying with all applicable laws.
Choosing the Right AR-10 80% Lower Receiver
Selecting the right AR-10 80% lower receiver involves considering several key factors:
Material:
- Aluminum: The most common material, offering a good balance of strength and weight.
- Polymer: Lighter and often less expensive than aluminum, but may not be as durable.
Manufacturer:
Research different manufacturers to find one with a reputation for quality and reliability. Look for reviews and feedback from other builders.
Features:
Some 80% lowers come with pre-machined features, simplifying the completion process. Consider whether this is a desirable feature for you based on your skill level and tools.
Completing Your AR-10 80% Lower Receiver
Completing an 80% lower receiver requires specialized tools and skills. This is not a project for beginners. Common tools needed include:
- Jig: A crucial tool for accurate and consistent machining. Different jigs are available for various machining methods.
- Mill/Drill Press: Precision machining is essential for proper functionality and safety.
- End Mills/Drill Bits: Appropriate tooling for the chosen machining method.
- Files/Sandpaper: For final finishing and smoothing.
Safety is paramount. Always wear appropriate safety gear, including eye protection, hearing protection, and a dust mask. Improper machining can lead to serious injury or a malfunctioning firearm.
Building Your AR-10: Beyond the Lower Receiver
Once the lower receiver is completed, you'll need to acquire the remaining components to build your AR-10. This includes the upper receiver, barrel, bolt carrier group, handguard, and various other parts. Thorough research and understanding of the AR-10 platform are essential for a successful build.
Conclusion
Building an AR-10 from an 80% lower receiver is a significant undertaking that demands careful planning, adherence to local laws, and a commitment to safety. While it can offer substantial cost savings and customization opportunities, it's not a project to be taken lightly. Always prioritize safety and legal compliance throughout the entire process. This guide serves as a starting point for your research—further investigation and understanding are crucial before embarking on this project. Remember to consult relevant legal resources and experienced builders to ensure a safe and successful build.
