Description

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

The Polymer80 80% Lower Receiver and Jig Kit (LR-308) delivers the foundation for a custom large-frame build. This kit provides the essential components required to complete a raw 80% lower receiver, giving you the flexibility to assemble a precision rifle platform according to your specifications. Designed for the LR-308 pattern, this kit streamlines the finishing process with precision-machined jigs and high-quality polymer components.

Overview

This kit includes an unfinished 80% lower receiver machined from reinforced polymer, along with the dedicated jig system necessary to complete the receiver. The Polymer80 80% Lower Receiver and Jig Kit (LR-308) is engineered for builders who want to start with a blank slate and finish the lower to exact tolerances. The jig guides the drilling and routing operations required to convert the 80% blank into a functional lower receiver, compatible with standard LR-308 upper receivers and parts kits. This kit eliminates the guesswork from the build process by providing indexed alignment points and hardened steel drill bushings.

Features & Specs

• Manufacturer: Polymer80. Category: Build Kits. Includes unfinished 80% lower receiver and complete jig system for the LR-308 platform.
• Reinforced polymer construction with internal metal insert for trigger pin and hammer pin retention. Jig features hardened steel bushings for precise drilling alignment.
• Compatible with standard LR-308 lower parts kits, buffer tubes, and stocks. Jig re-usable for multiple builds when combined with replacement jig plates (sold separately).
• Requires basic shop tools: drill press or hand drill, router or Dremel tool, and common hand tools. Detailed instructions included with the kit.

• Material: Impact-resistant polymer with stainless steel trigger pin insert.
• Fire control pocket dimensions machined to mil-spec tolerances for LR-308 pattern.
• Jig includes three-axis alignment system for drilling trigger pin, hammer pin, and safety selector holes.

Who It’s For

This kit is intended for individuals who possess the mechanical skills and tooling to complete a firearm receiver from an 80% blank. The Polymer80 80% Lower Receiver and Jig Kit (LR-308) suits experienced builders who want to customize their large-frame rifle without purchasing a completed lower. It is also appropriate for those who own standard LR-308 uppers and wish to match them with a compatible lower built to their preferred trigger group and stock configuration. This kit is not recommended for first-time builders without prior experience using drill presses or routers on polymer components.

Shipping & FFL

This product ships directly to your residence or business address. No Federal Firearms License (FFL) transfer is required for the 80% lower receiver because it is not classified as a firearm under federal law. However, once you complete the receiver by drilling the fire control pocket and installing the trigger group, the completed lower receiver becomes a firearm and must be serialized in accordance with all applicable federal, state, and local laws. It is your responsibility to verify that finishing an 80% lower receiver is legal in your state and municipality. Some states and localities restrict or prohibit the ownership or finishing of 80% receivers. Check your local laws before ordering.

• No FFL required for the unfinished 80% lower receiver.
• Complete the receiver at your own risk and in compliance with all laws.
• We do not provide legal advice; consult an attorney if you have questions about your jurisdiction’s requirements.