Polymer80 Rl556v3 – Rhino 80% Ar15 Lower Receiver Only

The Polymer80 RL556V3 – Rhino 80% AR15 Lower Receiver Only represents a precise, un-machined platform for builders who demand control over their firearm’s final configuration. This 80% lower receiver requires finishing by the end user, allowing for a custom serialization process that complies with all applicable federal regulations when completed for personal use. Constructed from high-impact polymer, the RL556V3 offers a lightweight foundation that reduces overall rifle weight without sacrificing structural integrity. As a manufacturer-direct component from Polymer80, this receiver is engineered to interface with standard AR15 parts kits, ensuring compatibility with a wide range of upper receivers, triggers, and buffer systems. The Rhino series designation reflects an enhanced ergonomic profile that improves handling during assembly and operation. For builders seeking a cost-effective starting point, the Polymer80 RL556V3 – Rhino 80% AR15 Lower Receiver Only delivers a reliable base that requires no serial number for personal builds, though buyers must verify local laws regarding unserialized receivers. This product is sold as a raw, unfinished part intended for hobbyist fabrication, not as a functional firearm.

Overview

The Polymer80 RL556V3 – Rhino 80% AR15 Lower Receiver Only is a semi-finished component that puts the builder in full control of the final product. Unlike fully completed lowers, this receiver requires drilling of trigger pin holes, hammer pin holes, and safety selector holes, along with milling of the fire control pocket. The polymer material provides a corrosion-resistant platform that remains stable under standard firing conditions. This lower receiver is designed to accept mil-spec AR15 lower parts kits and is compatible with both standard and drop-in trigger groups. The Rhino variant features an integrated trigger guard and a flared magazine well for improved reloading speed. Each receiver is manufactured to tight tolerances, ensuring that the finished product functions reliably when properly completed. The Polymer80 RL556V3 – Rhino 80% AR15 Lower Receiver Only includes a jig alignment block for use with optional drilling templates, though jigs are sold separately. This product requires no Federal Firearms License (FFL) transfer for purchase, as it is not classified as a firearm by the ATF when sold in its 80% state.

Features & Specs

• Material: High-impact, glass-reinforced polymer composite for lightweight durability; dimensions match mil-spec AR15 lower receiver geometry
• Compatibility: Accepts standard AR15 lower parts kits, buffer tubes, and pistol grips; compatible with most commercial and mil-spec upper receivers
• Design: Integrated trigger guard eliminates separate installation; flared magazine well for faster reloads; textured grip surface for secure handling

• Machining requirements: End user must complete fire control pocket milling, trigger/hammer pin hole drilling, and safety selector hole drilling; recommended use of Polymer80 jig kit
• Weight: Approximately 8.5 ounces, reducing overall rifle weight by 20% compared to aluminum lowers
• Finish: Matte black texture with no coating required; resistant to solvents, oils, and environmental exposure

• Manufacturer: Polymer80 – Rhino series; made in the USA
• Category: Parts – 80% lower receiver, non-firearm component
• Includes: One (1) Polymer80 RL556V3 – Rhino 80% AR15 Lower Receiver Only; no jig, bits, or instructions included

Who It’s For

The Polymer80 RL556V3 – Rhino 80% AR15 Lower Receiver Only is intended for experienced hobbyists, gunsmiths, and DIY builders who possess the tools and knowledge to complete a lower receiver from an 80% state. This product suits individuals who prefer to customize their firearm’s trigger, stock, and grip configuration from the ground up. It is also appropriate for those who wish to build a firearm for personal use without a serial number, in jurisdictions where such construction is legal. Builders should have prior experience with drilling and milling operations on polymer materials, as errors can render the receiver unusable. This lower is not recommended for first-time builders unless they have access to professional guidance or a complete instructional jig system. The Rhino design appeals to users who value ergonomic improvements, such as the flared mag well and integrated trigger guard, over standard lower profiles. Always consult local, state, and federal laws before purchasing or building with any 80% lower receiver.

Shipping & FFL

This Polymer80 RL556V3 – Rhino 80% AR15 Lower Receiver Only ships directly to your doorstep. No Federal Firearms License (FFL) transfer is required for purchase or delivery because this product is classified as a non-firearm component by the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) in its unfinished state. Standard shipping rates apply, and we ship to all US states where possession of 80% lower receivers is legal. However, it is your sole responsibility to verify that your local laws permit the possession, completion, and use of unserialized lower receivers. Some states, including but not limited to California, New York, New Jersey, Connecticut, Hawaii, and Washington, have restrictions on 80% receivers or require serialization upon completion. By purchasing this product, you confirm that you are legally allowed to possess and complete an 80% lower receiver in your jurisdiction. We do not provide legal advice, and we recommend consulting with a qualified attorney before beginning any build. All sales are final; no returns are accepted on partially or fully completed receivers.