Polymer80 80% Lower Receiver and Jig Kit (LR-308) – .308

Description

Product Overview

The Polymer80 80% Lower Receiver and Jig Kit for the LR-308 platform represents a significant evolution in the world of modern sporting rifle customization. Designed for the experienced firearms enthusiast, this kit provides the foundational component for building a lightweight, semi-automatic rifle chambered in .308 Winchester/7.62x51mm NATO. At its core, this is an 80% lower receiver, meaning it is not a completed firearm and requires machining to become functional, offering a deeply personalized project for those who value the build process itself. The primary use is to create a custom, DPMS-pattern AR-10 style rifle that prioritizes a drastic reduction in overall weight without sacrificing the robust functionality of the .308 caliber platform. This product is intended for builders who understand firearm regulations, possess the necessary tools and skills for completion, and seek to construct a uniquely maneuverable large-frame AR.

Key Features

• Ultralight Polymer Construction: Weighing in at less than half a pound, this receiver tackles the traditional heaviness of the AR-10/.308 platform head-on, enabling the construction of a remarkably lightweight and balanced rifle.
• DPMS-Pattern Compatibility: Engineered to the widely adopted DPMS specifications, ensuring broad compatibility with a vast array of AR-10 parts, uppers, components, and accessories available on the market.
• Integrated Jig System: The included precision jig is specifically designed for this polymer lower, providing the necessary guidance for accurate drilling and milling to complete the fire control group pocket, ensuring a proper fit for trigger components.
• Reinforced Design: Polymer80 utilizes high-strength, fiber-reinforced polymer in critical stress areas, such as the buffer tower and takedown pin lobes, to ensure durability and reliable performance under the recoil impulse of the .308 cartridge.
• Stripped 80% Lower Status: As an unfinished receiver blank, it is not classified as a firearm upon purchase, facilitating direct shipment in most jurisdictions. The completion process is a hands-on project for the qualified individual.
• Enhanced Ergonomics: The polymer frame can contribute to a more forgiving and comfortable handling experience, especially in variable weather conditions, compared to traditional aluminum receivers.

Performance & Applications

The completed Polymer80 LR-308 lower receiver is built for scenarios where weight savings directly translate to enhanced performance. One primary application is for a dedicated hunting rifle. A hunter covering long distances in mountainous or wooded terrain will appreciate a .308-capable platform that sheds significant weight, reducing fatigue and improving carry comfort without downsizing cartridge power. The reduction in weight also makes the rifle quicker to shoulder and maneuver in dense brush.

Another key use case is for a dynamic range or competition rifle. In practical shooting sports that involve movement, multiple target engagements, and positional shooting, a lighter large-frame AR reduces shooter fatigue, potentially leading to faster transitions and improved control during sustained strings of fire. The semi-automatic action allows for rapid follow-up shots, while the customizable nature of the platform lets the shooter tailor ergonomics, trigger, and stock to their exact preferences.

Finally, this lower serves as an ideal foundation for a lightweight, general-purpose rifle. For users who value a versatile, hard-hitting platform for recreational shooting, training, or preparedness, the weight savings make the rifle more accessible and easier to handle for a wider range of users, while maintaining the proven reliability and part commonality of the AR-10 system.

About Polymer80

Polymer80 has established itself as a forward-thinking leader in the firearms manufacturing space, specifically known for pioneering advanced polymer frame technology for modern sporting rifles and pistols. The company’s expertise lies in engineering high-strength polymer formulations and precision molds to create durable, reliable, and innovative receiver platforms. Their focus on the 80% market segment demonstrates a commitment to providing options for the knowledgeable hobbyist and builder community. Polymer80 invests significantly in research and development, as evidenced by products like the Warrhogg LR-308 lower which directly address long-standing platform limitations like weight. Their reputation is built on providing quality, consistent products that meet specific engineering challenges, backed by a deep understanding of materials science and firearm design principles.

Why Buy From F1 Firearms AR-15

Selecting a reputable retailer is as important as selecting the right component. Sourcing your Polymer80 kit from F1 Firearms AR-15 in Spring, TX, means purchasing from a specialist with direct industry knowledge. Their team understands the nuances of build kits, compatibility, and the requirements for a successful project. As a known entity with a physical presence and a focus on the AR platform, including their own F1 Firearms FDR-15 line, they provide a level of product curation and customer service informed by hands-on experience. This expertise ensures you receive the correct product and can access informed support for your build-related questions.

Make Your Decision

The Polymer80 LR-308 80% Lower and Jig Kit is a specialized tool for a specific builder. If your goal is to construct a uniquely lightweight, customizable, and capable .308 semi-automatic rifle and you possess the technical skill to complete the receiver safely and correctly, this kit offers a compelling solution. It directly addresses the historic weight penalty of the AR-10 platform, opening new possibilities for rifle handling and balance. Evaluate your tools, your understanding of the machining process, and your local laws. For the prepared builder, this kit is a pathway to a highly personalized and performance-oriented firearm.

Technical Specifications

Frequently Asked Questions