Kansas Gunshop is a Wichita, KS-based retailer specializing in AR-15 parts and accessories. The Polymer80 Rhino RL556v3 AR-15 80% Lower Receiver Kit Polymer Olive is a complete kit for building a polymer AR-15 lower. This kit includes all the necessary jigs and tooling. Available now for $450.0.
Reviewed by Derek, Owner & FFL Holder at Kansas Gunshop. Kansas-licensed FFL dealer since 2008, NRA Range Safety Officer.
Last updated: April 2026
What exactly is the Polymer80 Rhino RL556v3 AR-15 80% Lower Receiver Kit?
The Polymer80 Rhino RL556v3 AR-15 80% Lower Receiver Kit in Polymer Olive is designed for individuals looking to complete their own AR-15 lower receiver at home. This isn’t a stripped lower you’d get from your local FFL; it’s an 80% receiver, meaning it’s not yet considered a firearm by the ATF. You get the polymer lower itself, a jig, and all the necessary drill bits and end mill to finish the fire control group pocket, trigger pin holes, and selector switch hole. It’s a hands-on project that results in a functional AR-15 lower, ready for your choice of upper receiver and parts kit.
| Product Type | 80% AR-15 Lower Receiver Kit |
|---|---|
| Material | Proprietary Polymer Blend |
| Manufacturing | Injection Molded |
| Finish | Olive Drab Green (OD Green) |
| Hardness/Quality | Reinforced polymer for durability |
| Compatibility | Mil-spec AR-15 components (upper receivers, lower parts kits) |
| Installation/Usage | Requires user-machining to complete (jig and tooling included) |
| Weight | Approximately 4.5 oz (lower receiver only, unfinished) |
| Dimensions | Standard AR-15 lower dimensions |
| Country of Origin | USA |
| Condition | New |
| SKU | P80-RL556V3-ODG |
What are the key features of this Polymer80 kit?
- Integrated Trigger Guard: The trigger guard is molded directly into the lower, providing strength and a clean look. No need to install a separate trigger guard.
- Reinforced Buffer Tube Area: The area where the buffer tube threads in is strengthened to handle recoil and stress.
- Flared Magwell: The magwell is slightly flared to assist with quicker and smoother magazine changes.
- Picatinny Rail Section: A small Picatinny rail section is molded into the front of the magwell, allowing for accessories like a forward grip or light.
- Complete Kit: Includes the 80% lower, jig, drill bits, and end mill. This means you don’t have to source additional tools to complete the machining process, beyond a drill press or router.
- Aggressive Texturing: The grip areas feature a textured surface for better handling.
Who should consider buying this 80% lower kit?
Buy it if:
- ✅ You want to build an AR-15 from the ground up and enjoy the process of completing the lower yourself.
- ✅ You’re looking for a lightweight alternative to an aluminum lower receiver.
- ✅ You appreciate the integrated features like the trigger guard and flared magwell.
- ✅ You want the flexibility to build a rifle or pistol without the initial FFL transfer paperwork for the lower receiver itself.
- ✅ You’re interested in the Olive Drab Green color for your build.
Skip it if:
- ❌ You prefer a factory-finished, ready-to-assemble lower receiver. See our stripped lower receivers for alternatives.
- ❌ You don’t have access to a drill press or a router, or the patience for machining.
- ❌ You prefer the rigidity and feel of an aluminum lower receiver.
- ❌ You plan to build a rifle that will see heavy, sustained use where maximum durability is a primary concern.
How does it compare to other 80% lowers?
| Feature | Polymer80 Rhino RL556v3 (Polymer) | Generic Aluminum 80% Lower (Budget) | Aero Precision M4E1 80% Lower (Premium Aluminum) |
|---|---|---|---|
| Material | Proprietary Reinforced Polymer | 6061-T6 Aluminum | 7075-T6 Forged Aluminum |
| Quality | Good for polymer, integrated features | Basic, functional | High-grade, precision machined |
| Compatibility | Mil-spec AR-15 components | Mil-spec AR-15 components | Mil-spec AR-15 components, enhanced features |
| Shipping | Direct to consumer (no FFL required) | Direct to consumer (no FFL required) | Direct to consumer (no FFL required) |
| Lifespan/Durability | Good for recreational use, lighter duty. Polymer can be susceptible to extreme heat/cold cycling or harsh solvents over time. | Durable, standard aluminum lower | Very durable, built for demanding use |
| Price | ~$450.0 (kit with jig) | ~$60-80 (lower only, jig separate) | ~$250+ (lower only, jig separate) |
Frequently Asked Questions about the Polymer80 Rhino RL556v3 Kit
Is the Polymer80 Rhino RL556v3 considered a firearm?
No, the Polymer80 Rhino RL556v3 is an 80% lower receiver, meaning it is not yet legally considered a firearm by the ATF. It requires machining by the end-user to become a functional lower receiver. Once completed, it is then considered a firearm.
What tools do I need to complete this 80% lower?
The Polymer80 Rhino RL556v3 kit includes the necessary jig, drill bits, and end mill. You will need a drill press or a router to perform the machining operations. A vise to hold the jig securely is also highly recommended.
What kind of AR-15 parts are compatible with this lower?
This Polymer80 lower is designed to be compatible with standard Mil-spec AR-15 upper receivers and lower parts kits. You can use most common AR-15 components with it.
Can I use this for a pistol build or a rifle build?
Yes, once completed, this 80% lower can be used for either an AR-15 pistol build or an AR-15 rifle build, depending on the other components you choose and compliance with all applicable federal, state, and local laws.
Is a polymer lower as durable as an aluminum lower?
While modern polymer lowers are quite durable for most recreational shooting, they generally will not withstand the same level of abuse or extreme conditions as a forged 7075-T6 aluminum lower. Polymer is lighter and can absorb some recoil differently, but aluminum offers superior rigidity and resistance to heat and impact.
Where can I buy AR-15 80% lower receiver kits online?
You can purchase the Polymer80 Rhino RL556v3 AR-15 80% Lower Receiver Kit Polymer Olive right here at Kansas Gunshop (kansas-gunshop.com). We ship these kits directly to your door, as they are not serialized firearms.
What’s the benefit of an integrated trigger guard?
An integrated trigger guard means there’s no separate part to install, which simplifies assembly slightly and removes potential points of failure or looseness. It also contributes to the overall strength of the lower receiver in that area.
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✅ 30-day returns
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