Polymer80 RL556V3 – RHINO 80% AR15 Lower Receiver ONLY

Description

Product Overview

For the modern firearm enthusiast seeking a hands-on building experience, the Polymer80 RL556V3 – RHINO 80% AR15 Lower Receiver presents a compelling entry point. This product is an 80% lower receiver, meaning it is not a firearm as sold and requires machining to completion by the end-user, in compliance with all applicable laws. Designed specifically for the DIY builder, the RHINO is crafted from a high-strength polymer, making it an ideal project for those new to the world of firearm assembly or for experienced builders looking for a lightweight, durable alternative to traditional aluminum. Its primary use is to serve as the foundational component for a custom-built AR-15 style semi-automatic rifle, tailored to the builder’s specific preferences for triggers, stocks, and upper receivers.

Key Features

• Glass-Reinforced Nylon Composite Frame: Constructed from the same robust polymer material used in high-stress handgun frames, this lower receiver offers exceptional toughness and impact resistance while remaining significantly lighter than its aluminum counterparts.
• Beginner-Friendly Machining: The polymer material is far easier to cut, drill, and finish than aluminum, requiring only basic workshop tools like a drill press or hand drill and a router. This lowers the barrier to entry for first-time builders.
• Threadless Pistol Grip Design: An improvement over prior models, this feature eliminates threaded stress points within the receiver area, enhancing the structural integrity and long-term durability of the frame under recoil.
• RL556v3 Enhanced Design: This iteration incorporates refinements based on user feedback and engineering analysis, focusing on improved reliability and a more user-friendly finishing process for the fire control cavity.
• Compatible with Standard AR-15 Parts: The RHINO is designed to accept most mil-spec AR-15 upper receivers, lower parts kits, triggers, and buffer assemblies, ensuring broad compatibility for customization.
• Semi-Automatic Action Platform: When completed and assembled with a proper upper receiver, it is designed to function as a semi-automatic rifle, adhering to all standard operating mechanisms of the AR-15 platform.

Performance & Applications

The Polymer80 RHINO is engineered for specific builder profiles and applications where its polymer construction offers distinct advantages. Its performance is rooted in practical, real-world use cases.

1. The First-Time Builder’s Educational Project: This lower is an excellent choice for individuals interested in learning the mechanical intricacies of the AR-15 platform. The relative ease of machining polymer allows a newcomer to focus on the learning process—understanding the function of each pin, spring, and lever—without the need for expensive metalworking tools. The completed build results in a functional rifle and, more importantly, a deep, practical knowledge of its operation and maintenance.

2. The Lightweight Dedicated Build: For builders constructing a rifle where minimizing weight is a critical factor—such as for extended carry in hunting scenarios or for a dedicated .22LR training rifle—the RHINO provides a significant weight reduction at the receiver. When paired with a lightweight upper and stock system, it contributes to a remarkably agile and easy-to-handle firearm.

3. The Specialized Custom Range Rifle: Enthusiasts looking to build a highly customized rifle for specific range disciplines can use the RHINO as a cost-effective foundation. The savings on the receiver itself can be allocated toward premium components like a match-grade trigger, a precision barrel, or advanced optics, creating a tailored tool for target shooting without compromising on core component quality.

About Polymer80

Polymer80 has established itself as a leading innovator in the DIY firearm component market through a steadfast commitment to engineering and user empowerment. The brand’s expertise is demonstrated by its focused material science, particularly in advanced polymer formulations. Their use of glass-reinforced nylon composites isn’t a cost-cutting measure, but a deliberate engineering choice to create products that meet specific performance criteria for durability, weight, and user accessibility.

The company’s authority is built on a track record of iterative design. The “v3” designation on the RL556V3 Rhino is a direct signal of this; it represents a product refined through real-world feedback and continuous improvement. Polymer80 provides clear, detailed instructions and support for their products, emphasizing responsible building practices and compliance. This combination of practical design, quality control, and educational support fosters trust within the building community, making them a go-to source for both novice and experienced fabricators seeking reliable components.

Make Your Decision

The Polymer80 RL556V3 RHINO 80% Lower Receiver is a thoughtfully engineered component that democratizes the AR-15 building process. It represents a clear choice for the builder who prioritizes a manageable machining project, desires the benefits of a lightweight polymer frame, and trusts in a brand known for continuous refinement. Consider this lower if your goal is to gain hands-on experience or to create a lightweight, custom rifle with a focus on practical performance. Ensure you understand and are prepared to undertake the finishing work required in compliance with all federal, state, and local laws before making your purchase.

Technical Specifications

Frequently Asked Questions