Description

Polymer80 RL556V3 – Rhino 80% AR15 Lower Receiver Only

Build your next AR15 platform from the ground up with the Polymer80 RL556V3 – Rhino 80% AR15 Lower Receiver Only. This unfinished lower receiver is engineered for the serious builder who demands a lightweight, durable foundation without compromising on precision. Crafted from high-impact polymer, the RL556V3 offers the structural integrity of aluminum at a fraction of the weight, making it an ideal choice for custom builds where mobility and reliability are paramount.

Overview

The Polymer80 RL556V3 – Rhino 80% AR15 Lower Receiver Only is a pre-machined, unfinished lower that requires final milling to complete. It is designed to accept standard AR15 lower parts kits and buffer tubes, giving you total control over your build’s ergonomics and aesthetics. The 80% configuration means you can finish this receiver at home with basic tools, provided you comply with all applicable federal, state, and local laws. This receiver is not a firearm until fully machined, making it a legal starting point for hobbyists and custom builders.

Features & Specs

• Manufacturer: Polymer80 | Category: Parts | Material: High-strength polymer composite with integrated steel reinforcement blocks
• Designed for standard AR15 lower parts kits (LPK) and buffer tube assemblies; compatible with mil-spec uppers
• Integrated trigger guard, flared magazine well for faster reloads, and textured grip area for improved control
• Pre-drilled pin holes and indexing marks for jig-guided milling; includes all necessary hardware for jig alignment
• Weight: approximately 8.2 ounces (unfinished) – significantly lighter than aluminum counterparts

Who It’s For

The Polymer80 RL556V3 – Rhino 80% AR15 Lower Receiver Only is built for the hands-on enthusiast who values customization over off-the-shelf solutions. Whether you are a first-time builder seeking a lightweight recoil-friendly platform or an experienced gunsmith looking to experiment with polymer frames, this receiver offers a blank canvas. It is not recommended for users who prefer fully assembled lowers or who are unwilling to invest the time in proper finishing and assembly. This is a parts-level component intended for builders who understand the mechanical and legal responsibilities of completing a firearm.

• Ideal for lightweight hunting rifles, competition builds, or tactical carbines where weight savings matter
• Suitable for builders who own or have access to a standard 80% lower jig and router or drill press
• Not for those seeking a drop-in, ready-to-fire lower receiver; requires finishing and assembly

Shipping & FFL

Because the Polymer80 RL556V3 – Rhino 80% AR15 Lower Receiver Only is an unfinished 80% receiver, it is not classified as a firearm by the ATF. Therefore, it ships directly to your home or business address with no FFL transfer required. However, it is your sole responsibility to verify that finishing this receiver into a functional firearm is legal in your state, county, and municipality. Some jurisdictions restrict or prohibit the manufacture of unserialized firearms. By purchasing this product, you confirm that you are legally permitted to possess and complete an 80% lower receiver in your area. We do not provide legal advice; consult an attorney if you have any doubts.

• No FFL transfer needed for this unfinished receiver; ships to any residential or commercial address
• Local laws vary; check your state and local regulations before ordering
• You must be 18 years or older to purchase this product