A Complete Guide to 80% Lowers: What You Need to Know

The world of firearms is continually evolving, and one of the more exciting trends in recent years is the rise of 80% lowers. These unfinished lower receivers have gained considerable attention among gun enthusiasts, hobbyists, and those looking to assemble their firearms from the ground up. Whether you’re a DIY builder, an enthusiast of gun customization, or simply someone looking to save money on a firearm, 80% lowers offer a unique and interesting opportunity.

In this comprehensive guide, we will explore what 80% lowers are, how they work, their legal status, the benefits of building a firearm from an 80% lower, and much more. By the end of this article, you will have a complete understanding of these fascinating components and how to incorporate them into your firearm-building projects.

What Are 80% Lowers?

In simple terms, 80% lowers are partially completed lower receivers that can be purchased by anyone legally allowed to own firearms. These parts are essentially “unfinished” and require further machining and assembly to become fully functional components of a firearm. The term “80%” refers to the fact that the lower receiver is 80% finished when sold, leaving the remaining 20% of machining work to the buyer.

These unfinished receivers are most commonly used in the assembly of AR-15 and AR-10 style rifles, but they can also be found in various other firearms like shotguns and handguns. The fact that these parts are unfinished means they are not classified as firearms until they are fully completed, which allows buyers to purchase them without undergoing the usual background checks or paperwork required for a fully functional firearm.

Types of 80% Lowers

There are two primary types of 80% lowers that enthusiasts commonly use:

  1. AR-15 Lowers: The most common type of 80% lower, used in the construction of the popular AR-15 rifles. These lowers are compatible with various calibers and offer a wide range of customization options for builders.
  2. AR-10 Lowers: These are the larger versions of the AR-style receivers, used in the construction of .308 and other large-caliber rifles. While less common than AR-15 lowers, 80% AR-10 lowers are growing in popularity due to the increased interest in precision long-range rifles.

Though these are the most common, 80% lowers can also be found for other firearms, including pistols, shotguns, and even more exotic designs.

How Does an 80% Lower Work?

The process of turning an 80% lower into a functioning firearm component requires specific tools, skills, and attention to detail. Essentially, these lowers come almost ready for assembly but still need a final bit of machining to allow parts such as triggers, pins, and other mechanisms to fit into place.

The process of completing an 80% lower typically involves:

  • Drilling holes for various components such as the trigger, hammer, pins, and selector switch.
  • Milling out the fire control cavity, which houses the trigger and other moving parts.
  • Finishing the receiver to the correct dimensions for proper fitment and functionality.

What Tools Are Required?

To complete an 80% lower, the following tools are commonly needed:

  • Drill Press: For precise hole drilling.
  • End Mills: To mill out the fire control cavity and other areas that require material removal.
  • Jig: A guiding system that helps ensure the drilling and milling are done accurately.
  • Various Drill Bits and Cutting Tools: Required for drilling holes and milling out necessary areas.

The process is not necessarily difficult, but it does require precision and patience. Many gun builders purchase 80% lower completion kits that come with all the necessary tools and jigs to help streamline the process.

Legal Considerations of 80% Lowers

One of the key reasons why 80% lowers have gained so much attention is their legal status. While a fully completed firearm requires a background check and federal paperwork, an 80% lower does not. This is because, under U.S. law, a firearm is not considered a “firearm” until it has reached a certain level of completion, which includes the installation of necessary components such as the trigger, hammer, and buffer tube.

Federal Law and the ATF

According to the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF), 80% lowers are not considered firearms until they are fully completed. This means they are not subject to the same regulations that govern the sale and possession of fully functional firearms. As a result, you can purchase an 80% lower without undergoing a background check, and it can be shipped directly to your home. However, once you finish the machining and assemble the parts into a complete firearm, it is considered a legal firearm and must be treated as such.

The ATF does not require you to register firearms made for personal use, but you are prohibited from selling them without the proper licensing. If you intend to sell firearms that you have built from 80% lowers, you will need a Federal Firearms License (FFL) and must comply with federal and state regulations.

State and Local Regulations

While 80% lowers are legal under federal law, some states and localities have stricter rules governing unfinished firearm components. States like California, New York, and New Jersey have more restrictive laws when it comes to buying and completing 80% lowers, and some have outright banned their sale or possession.

In addition to state laws, some cities or counties may have local ordinances that regulate or ban the sale of these parts. Before purchasing an 80% lower, it is crucial to familiarize yourself with the specific laws in your area to ensure compliance.

The Advantages of Using 80% Lowers

Building your own firearm from an 80% lower can offer a number of benefits. These advantages include customization options, cost savings, and the educational experience that comes with building a firearm from scratch.

1. Customization and Personalization

When you build a firearm from an 80% lower, you have complete control over the configuration and design of the weapon. Whether you want a lighter build, a specific stock or grip, or any other customization, you have the ability to select the parts that best suit your needs and preferences.

From barrel length to trigger type, the possibilities for customization are nearly endless. For gun enthusiasts who appreciate the ability to personalize their firearms, building from an 80% lower allows them to create something truly unique.

2. Cost Savings

Another major advantage of 80% lowers is the potential for cost savings. Pre-assembled firearms, especially high-quality ones, can be quite expensive. By purchasing an 80% lower and completing the machining and assembly yourself, you can save money on the raw component, which often costs less than a fully assembled firearm.

While there will be some upfront costs for tools and equipment, in the long run, building your own firearm can be more cost-effective than buying a ready-made gun.

3. Knowledge and Skill Development

Building a firearm from an 80% lower is not just about assembling parts—it’s about developing knowledge and hands-on skills. As you work on the lower receiver, you’ll learn how firearms function and how different components interact with each other. This experience can be invaluable, whether you’re interested in gunsmithing, repairing firearms, or simply improving your understanding of the mechanics behind your firearms.

4. Satisfaction of Building Your Own Firearm

There is something immensely satisfying about building your own firearm from an 80% lower. The sense of accomplishment that comes with completing your own gun is something that many hobbyists cherish. Whether it’s for recreational use, hunting, or home defense, knowing that you built the firearm yourself can enhance the overall ownership experience.

Step-by-Step Process for Completing an 80% Lower

For those interested in completing an 80% lower, the following is a general overview of the process:

Step 1: Prepare Your Tools and Workspace

Before starting, ensure you have all the necessary tools, including a drill press, end mills, jigs, and safety equipment. Your workspace should be clean, organized, and well-lit to ensure accuracy and safety during the process.

Step 2: Install the Jig

The jig will guide the drilling and milling process. It is essential for ensuring that the holes are drilled in the correct places and that the fire control group cavity is milled out properly. Carefully follow the instructions provided with the jig to set it up correctly.

Step 3: Drill the Necessary Holes

Use the drill press and appropriate bits to drill the holes for the trigger pins, hammer pins, and other necessary parts. Accuracy is key in this step, as misaligned holes can result in a malfunctioning firearm.

Step 4: Mill the Fire Control Cavity

This is one of the most critical steps in completing an 80% lower. The fire control cavity must be milled out to the correct dimensions to accommodate the trigger, hammer, and other moving parts. Precision in this step is essential to ensure that the firearm functions correctly.

Step 5: Final Checks and Assembly

Once the machining is complete, carefully inspect the lower receiver for any issues. Check the fit of all the parts and make sure everything is properly aligned. After ensuring the lower receiver is complete, you can begin assembling the remaining components of your firearm.

Common Myths About 80% Lowers

Myth 1: 80% Lowers Are Unregulated

While it’s true that 80% lowers are not considered firearms by the ATF until they are fully completed, they are still subject to state and local regulations. Always verify your local laws before purchasing or completing an 80% lower.

Myth 2: Anyone Can Build a Firearm

Building a firearm from an 80% lower requires a certain level of skill and precision. While it’s not extremely difficult, the process involves using tools such as drill presses and milling machines, which require technical knowledge to operate effectively.

Myth 3: The Process is Cheap and Easy

While 80% lowers themselves are often cheaper than fully assembled firearms, completing them is not without cost. There are tool costs, and it takes time and effort to get the machining done correctly. It’s not a project to be taken lightly, but for those who are willing to put in the work, it can be highly rewarding.

Conclusion

The appeal of 80% lowers lies in their potential for customization, the opportunity to save money, and the satisfaction of building a firearm yourself. While the process of completing an 80% lower is not without its challenges, it is a highly rewarding experience for those who are interested in firearms and DIY projects. However, it’s important to remember that the legal status of these lowers varies by location, and it’s crucial to be informed about the laws in your area before proceeding with any builds.

For those who take the time to understand the process and follow safety protocols, building a firearm from an 80% lower can be a fulfilling and educational journey that offers lasting satisfaction. So, if you’re considering diving into the world of 80% lowers, make sure you’re well-prepared and ready to embark on an exciting and enriching project.

Similar Posts

Leave a Reply

Your email address will not be published. Required fields are marked *