Description

Polymer80 LR-308 80% Lower Receiver

The Polymer80 LR-308 80% lower receiver represents a foundational component for builders pursuing a large-frame AR pattern platform. Designed for the .308 Winchester / 7.62 NATO cartridge family, this receiver is manufactured from a proprietary reinforced polymer blend engineered to withstand the increased cyclic forces and chamber pressures associated with full-power rifle cartridges. As an 80% completion component, it requires final machining of the trigger pocket, fire control group pin holes, and selector detent channels prior to assembly. This product is intended for individuals who possess the tooling, technical knowledge, and legal capacity to complete an unfinished receiver under applicable federal and state regulations.

Overview

The Polymer80 LR-308 80% lower receiver is a direct adaptation of the company’s proven polymer molding technology for the DPMS-pattern LR-308 platform. Unlike standard AR-15 lowers, this receiver features an enlarged magazine well and increased wall thickness to accommodate the longer action and higher bolt thrust of .308-class cartridges. The receiver body incorporates integral trigger guard geometry and a flared magazine opening for improved reload speed. Compatible with standard LR-308 / DPMS pattern upper receivers, this component streamlines the build process for a large-frame rifle while reducing overall weight compared to billet or forged aluminum counterparts.

Features & Specs

This receiver is manufactured from a glass-reinforced nylon polymer that provides structural rigidity while resisting impact and temperature extremes. The material formulation is specifically engineered to maintain dimensional stability under the recoil impulse of .308 Winchester loads. Key specifications include compatibility with standard LR-308 lower parts kits, DPMS-pattern buffer tubes, and AR-10 pattern magazines. The receiver is precision molded to SAAMI-specification dimensions for the fire control pocket, trigger pin holes, and takedown pin lugs. All critical surfaces are finished with a non-reflective textured surface that provides positive grip during handling and installation.

• Material: Glass-reinforced Zytel polymer composite with UV stabilizers
• Platform: LR-308 / DPMS pattern large-frame AR (.308 Winchester / 7.62 NATO)
• Completion Level: 80% – requires final machining of trigger pocket, hammer/trigger pin holes, selector detent, and safety selector channel
• Weight: Approximately 8.2 ounces (unfinished receiver only)
• Finish: Matte black textured surface, corrosion-resistant formulation

• Integrated trigger guard molded as single-piece with receiver body
• Flared magazine well opening for rapid reloading under stress
• Compatible with standard AR-10 / LR-308 lower parts kits from major manufacturers
• Accepts DPMS-pattern buffer tubes and collapsible stock assemblies
• Molded rear takedown pin detent channel with pre-drilled pilot for final machining

• Reinforced bolt catch pocket with steel insert compatibility
• Integral trigger guard eliminates separate component installation
• Pre-molded grip tang for standard AR-10 pistol grip compatibility
• Oversized trigger guard opening for use with gloves or cold weather gear
• Molded-in receiver extension threads (1-3/16″-16 TPI) for buffer tube attachment

Who It’s For

This polymer80 lr-308 80% lower receiver is intended for experienced firearm builders who possess the necessary machining equipment to complete an unfinished receiver. It is suitable for hobbyists constructing a dedicated long-range precision rifle, a heavy-barreled hunting platform, or a large-frame battle rifle clone. The component is also appropriate for individuals seeking to reduce overall rifle weight while maintaining the durability required for sustained .308 firing schedules. Builders should have prior experience with 80% lower completion techniques and understand the specific jig requirements for large-frame receivers. This product is not recommended for first-time builders or those without access to a drill press, end mill, or appropriate jig system designed for the LR-308 pocket geometry.

Shipping & FFL

Per Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) regulations, the polymer80 lr-308 80% lower receiver is not classified as a firearm and may be shipped directly to your residence or business address. No Federal Firearms License (FFL) transfer is required for purchase or delivery. However, it remains the buyer’s sole responsibility to verify that possession and completion of an unfinished receiver are legal under all applicable federal, state, and local laws. Some states and municipalities impose restrictions on the purchase, possession, or machining of 80% receivers. By placing an order, you confirm that you are legally eligible to possess this component and that you will comply with all applicable laws. We do not provide legal advice. If you have questions regarding your jurisdiction’s requirements, consult with a qualified attorney before purchase.