Description

Polymer80 RL556V3 – Rhino 80% AR15 Lower Receiver Only

Building your own AR-15 from the ground up gives you total control over fit, finish, and function. The Polymer80 RL556V3 – Rhino 80% AR15 Lower Receiver Only is the foundation for that kind of project. It’s an unfinished lower that lets you machine out the fire control pocket and trigger pin holes yourself, putting you in the driver’s seat from the start. Whether you’re after a lightweight build or just want to learn the platform inside and out, this receiver gives you a solid, no-nonsense starting point at a price that makes sense for any workshop.

Overview

The Polymer80 RL556V3 – Rhino 80% AR15 Lower Receiver Only is a polymer 80% lower designed for the home builder who values simplicity and affordability. Unlike aluminum billet lowers, this one uses a reinforced polymer construction that keeps weight down without sacrificing the critical dimensions you need for a reliable build. It comes as an 80% blank, meaning the main pocket and trigger channel are already formed, but you’ll need to complete the fire control group pocket and drill the trigger and hammer pin holes. This is a genuine Polymer80 product, not a clone, so you’re getting the same tolerances and material quality that the company is known for in the DIY firearms community. If you’ve been looking for a polymer80 rl556v3 – rhino 80% ar15 lower receiver only to start a lightweight or budget-conscious AR, this is it.

Features & Specs

This receiver is built around a glass-reinforced polymer that resists impact and maintains its shape under recoil. The V3 generation includes a reinforced takedown pin boss area and an integrated trigger guard, so you don’t have to buy or install a separate one. The magazine well is flared slightly for faster reloads, and the grip angle is standard AR-15 spec, meaning it works with nearly any aftermarket grip you prefer. Here’s what you’re working with:

• 80% completion level: fire control pocket is pre-formed, but you must machine out the trigger pocket floor and drill the trigger/hammer pin holes
• Reinforced polymer construction with stainless steel trigger pin inserts for long-term durability
• Integrated trigger guard and flared magazine well for improved handling and reload speed

Because this is a polymer80 rl556v3 – rhino 80% ar15 lower receiver only, it’s compatible with standard AR-15 upper receivers, parts kits, and buffer tubes. You’ll need a jig and basic tools to finish it, but the process is straightforward for anyone with a drill press or hand drill and a steady hand. The receiver accepts all standard AR-15 magazines and triggers, so you’re not locked into a proprietary system.

Who It’s For

This lower is ideal for the hands-on builder who wants to complete a firearm without the overhead of a full billet machining project. It’s a great choice if you’re building a lightweight hunting rifle, a range toy, or a truck gun where every ounce matters. The Polymer80 RL556V3 – Rhino 80% AR15 Lower Receiver Only also works well for someone who wants to learn the AR platform by finishing their own lower, rather than buying a completed one. If you’re a first-time builder, just take your time with the jig instructions and go slow on the drilling—this polymer cuts cleanly with sharp bits. It’s also a solid option for experienced builders who want a low-cost lower for a beater build or a project you don’t mind putting some miles on.

• Home builders and DIY enthusiasts who want to complete their own AR-15 lower
• Shooters looking for a lightweight alternative to aluminum lowers without giving up reliability
• Anyone wanting a budget-friendly foundation for a custom AR-15 build using standard parts

Shipping & FFL

Because this is an 80% lower receiver and not a completed firearm frame, it does not require transfer through a Federal Firearms License (FFL) dealer. It ships directly to your doorstep with no additional paperwork or transfer fees. However, once you complete the machining and assemble it into a functional firearm, you must comply with all applicable federal, state, and local laws regarding possession and serialization. Some states and localities have specific restrictions on 80% receivers or require serial numbers after completion. It is your responsibility to know and follow the laws in your area. We do not provide legal advice, and by purchasing this product you confirm that you are legally allowed to possess and finish an 80% lower receiver in your jurisdiction. If you have questions about compliance, consult a qualified attorney before beginning your build.

• No FFL transfer required for this 80% lower receiver
• Ships directly to your shipping address within the continental US
• You are solely responsible for complying with all state and local laws regarding completion and possession