Overview

A Polymer80 lower receiver for large-frame (AR-10 / LR-308 pattern) rifles in .308 Winchester / 7.62x51mm, made from polymer and supplied 80% complete. Receivers like this ship to your FFL dealer for transfer.

More about the Polymer80 LR-308 80% Lower Receiver

The Polymer80 LR-308 80% Lower Receiver is the foundational component for builders looking to create a customized, large-frame AR-platform rifle. Designed for the serious hobbyist, this receiver is a "blank" or unfinished part, requiring machining to be completed into a functional firearm component. It is engineered for the .308 Winchester/7.62x51mm NATO caliber, making it the core of a custom AR-10 build. Its primary use is for individuals who enjoy the hands-on process of gunsmithing, value the satisfaction of a personal build, and seek a lightweight alternative to traditional aluminum receivers. This product is ideal for experienced builders and, due to its user-friendly material, can also be a suitable project for first-time 80% builders who have done their research and understand the tools and process required.

Key Features

• Nylon-Reinforced Polymer Frame: Constructed from a proprietary, glass-reinforced polymer composite, this lower receiver offers a significant reduction in weight compared to aluminum counterparts while maintaining impressive durability and rigidity for reliable performance.
• .308/7.62 NATO Compatibility: Specifically machined to accept standard AR-10/.308 platform parts kits, upper receivers, and magazines, ensuring broad compatibility for your custom large-frame build.
• Optimized for Easy Machining: The polymer material is notably easier to drill and mill than aluminum, reducing wear on standard workshop tools and allowing for a more straightforward finishing process with a drill press or router jig.
• Lightweight Design: The polymer construction shaves critical ounces from your rifle's overall weight, a key consideration for building a hunting rig or a rifle intended for extended carry.
• Pre-Machined Critical Areas: Essential features like the fire control group pocket, trigger pin holes, and buffer tower are pre-formed, providing a precise guide for the builder and simplifying the final machining steps.
• Reinforced Stress Points: Strategic engineering and reinforcement in high-stress areas, such as the buffer tube interface and pivot/take-down pin lugs, ensure the receiver can handle the sustained pressures of the .308 cartridge.

About Polymer80

Polymer80 is a recognized leader in the modern firearms ecosystem, specializing in innovative frame and receiver solutions. The company has built its reputation on a deep understanding of polymer engineering and firearm design principles. Their expertise is demonstrated through rigorous testing and development, focusing on creating products that meet specific performance criteria for durability, ergonomics, and compatibility. Polymer80's commitment to the builder community is evident in their design philosophy, which prioritizes logical, user-friendly manufacturing processes without sacrificing strength or reliability. They have established authority in the market by consistently producing components that adhere to precise specifications, ensuring builders can complete their projects with confidence in the foundational part's integrity.