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

Overview

This Polymer80 80% Lower Receiver and Jig Kit (LR-308) is a precision-engineered solution for builders focused on the large-frame AR platform. Designed for the LR-308 pattern, this kit provides the core components necessary to complete a serial-number-free lower receiver at your own workbench. The kit includes a raw 80% lower receiver and a dedicated jig system that guides critical machining operations. For builders seeking a durable, lightweight foundation for a .308 or 6.5 Creedmoor build, this polymer80 80% lower receiver and jig kit (lr-308) represents a direct path to a custom large-frame firearm without the need for a pre-serialized receiver.

Features & Specs

Every component in this build kit is manufactured to tight tolerances by Polymer80, a recognized name in the 80% receiver market. The lower receiver is constructed from a high-impact polymer composite, offering significant weight savings over traditional aluminum receivers while maintaining structural integrity under recoil. The included jig system is precision-molded to align drill and end mill paths accurately, reducing the margin for error during the finishing process. This polymer80 80% lower receiver and jig kit (lr-308) is specifically dimensioned for DPMS-pattern LR-308 components, ensuring compatibility with standard lower parts kits, buffer tubes, and upper receivers.

• Receiver material: High-impact polymer composite, black finish
• Pattern: DPMS LR-308 / SR-25 compatible platform
• Includes: 80% lower receiver, multi-position jig, drill bits, end mill, and installation instructions
• Weight: Approximately 0.8 lbs for the complete kit

• Jig features hardened steel alignment bushings for repeatable drilling
• Fire control pocket is pre-molded to approximate final dimensions; final machining required
• Accepts all standard LR-308 LPKs, pistol grips, and buffer tube assemblies

Who It’s For

This kit is intended for experienced firearm builders who possess a stable work surface, a drill press or hand drill, and basic knowledge of 80% receiver finishing. It is not a beginner-level product. The polymer80 80% lower receiver and jig kit (lr-308) is designed for individuals who want to assemble a large-frame AR platform from the ground up, without purchasing a completed, serialized lower. This includes hobbyists, custom rifle builders, and shooters who prefer to control the entire build process from receiver to final assembly. If you are comfortable with measuring, drilling, and using a router or end mill, this kit provides the necessary components to complete a functional lower receiver.

• Ideal for builders with prior experience completing 80% lowers
• Suitable for those building a lightweight .308 or 6.5 Creedmoor hunting or target rifle
• Recommended for customers who want to avoid a serialized lower and prefer a DIY approach

Shipping & FFL

This Polymer80 80% Lower Receiver and Jig Kit (LR-308) is classified as an unfinished, non-firearm receiver blank. As such, it does not require transfer through a Federal Firearms License (FFL) dealer and can be shipped directly to your residential or business address in most states. However, it is your responsibility to verify that possession of 80% receivers is legal under all applicable federal, state, and local laws. Some jurisdictions impose restrictions on the purchase, possession, or finishing of unserialized receivers. By placing an order, you confirm that you are legally permitted to own this product in your location. No FFL transfer is required from our side, but we reserve the right to refuse shipment to any jurisdiction where such items are prohibited.