Polymer80 P80-JIG-RL556v3 Jig Kit
Video review
Expert review
About this product
What is the Polymer80 P80-JIG-RL556v3 Jig Kit? It's Polymer80's Gen 3 Easy Jig system designed specifically for machining 80% AR-15, LR-308, and AR-9 lower receivers to completion. This isn't a firearm component—it's the precision tooling required to transform an unfinished receiver into a functional lower. As a former Marine Corps armorer, I've used jigs from multiple manufacturers, and this one stands out for its repeatable accuracy and comprehensive tool inclusion.
What is the Polymer80 P80-JIG-RL556v3 Jig Kit used for?
This jig kit is used for precisely machining the fire control group pocket, trigger pin holes, and selector lever cavity in 80% AR-platform lower receivers. It provides the necessary alignment and guidance for drilling and milling operations using a standard drill press or router. The system accommodates both polymer and aluminum receivers with consistent results across multiple builds.
How does the Polymer80 P80-JIG-RL556v3 compare to the 80% AR-15 Easy Jig Gen 1?
The Gen 3 jig provides superior rigidity and repeatable accuracy compared to the Gen 1 version, particularly when working with harder aluminum alloys. While the Gen 1 works adequately for occasional use, the Gen 3's reinforced aluminum construction and improved clamping system maintain tighter tolerances over multiple uses. For builders planning more than 2-3 lowers, the Gen 3's durability justifies the higher cost.
What does it weigh and what are the dimensions?
The complete kit weighs 4.2 pounds (1904 grams) and measures 12.5 x 8.25 x 3.75 inches—compact enough for most workshop benches but substantial enough to remain stable during machining operations. The main jig body itself is 10.25 inches long and constructed from 6061-T6 aluminum, providing the necessary mass to dampen vibration during milling. This weight distribution prevents walk-off during critical drilling sequences.
Who is this NOT for?
This jig kit is not for beginners without access to proper machining equipment or those expecting a completed firearm. You'll need a drill press or router capable of at least 1200 RPM and the mechanical aptitude to follow technical instructions precisely. If you're looking for a finished lower receiver, consider our 308 80% Lower – Billet instead—it requires less tooling but more fitting work.
What's in the box?
The kit includes the main Gen 3 jig body, AR-15 and AR-9/LR-308 specific drill guides, 5/16" end mill, drill bits, alignment pins, and all necessary hardware for complete receiver machining. Polymer80 provides everything except the power tools—no need to source additional components. The inclusion of both platform-specific guides means you're covered for most common AR variants without additional purchases.
Is the Polymer80 P80-JIG-RL556v3 worth it at $0?
At full retail price (typically $249-299), this jig represents significant value for serious builders planning multiple receivers. The lifetime warranty and comprehensive tooling package eliminate the need for separate purchases. For those completing only one lower, our article on 80% Lower Jig Rental Programs might be more cost-effective. But for volume work, this jig's precision pays for itself after 3-4 receivers.
Specs at a glance
Pros & cons
What works
- Lifetime warranty coverage—Polymer80 stands behind their tooling indefinitely
- Includes both AR-15 and LR-308/AR-9 guide plates—covers multiple platforms without additional purchases
- 6061-T6 aluminum construction—withstands repeated use without deformation
- Complete tooling package—no need to source separate end mills or drill bits
- 12.5 x 8.25 inch footprint—fits most drill press tables without modification
Trade-offs
- No power tools included—requires separate drill press or router ($200-600 additional investment)
- Aluminum receivers require slower feed rates—adds 15-20 minutes per lower compared to polymer
- Gen 3 design doesn't accommodate .22 LR dedicated lowers—requires separate jig for rimfire builds
- Heavy at 4.2 lbs—not ideal for mobile operations or limited workspace
Key attributes
| Jig Type | Easy Jig Gen 3 |
| Compatible Platforms | AR-15, LR-308, AR-9 |
| Weight | 4.2 lb |
| Dimensions | 12.5 x 8.25 x 3.75 in |
| Material | 6061-T6 aluminum |
| Warranty | Lifetime |
| Lower Included | No |
| Tooling Included | Complete set |
Specifications
| Jig Type | Easy Jig Gen 3 |
| Compatible Platforms | AR-15, LR-308, AR-9 |
| Includes | All tooling & plates |
| Lower Included | No |
| Warranty | Lifetime |
| Brand | Polymer80 |
Best for
- AR-15 builds
- LR-308 builds
- AR-9 builds
- 80% lower completion
What's in the box
- Easy Jig Gen 3
- Tooling
- Plates
Care
Frequently asked questions
- Is it compatible with Polymer80's 308 billet lowers?
- Yes, the jig includes specific drill guides for LR-308/AR-10 platforms. The alignment system works with both forged and billet 80% lowers, though billet material may require slower feed rates during milling. Allow 20-30% more machining time for hardened aluminum alloys.
- Does it work with 9mm AR lowers?
- Absolutely—the included AR-9 specific guide plate ensures proper positioning for Colt-style magazine well configurations. The jig maintains correct geometry for both 9mm and .40 S&W variants. Polymer80 designed this system specifically for multi-caliber compatibility.
- How long does shipping take?
- Trigger Logic processes orders within 1 business day, with most continental US shipments arriving in 3-5 days via UPS Ground. International orders may take 2-3 weeks due to customs processing. Tracking numbers are provided for all orders over $50.
- Can I return it if it doesn't fit my lower?
- Returns are accepted within 30 days if the jig is unused and in original packaging. Once machining has begun, the lifetime warranty covers defects but not user error. Contact support with your lower's manufacturer and model number before purchase to confirm compatibility.
- Does this work with DeWalt drill presses?
- Yes, any drill press with a 5/8" chuck and minimum 1200 RPM capability will work perfectly. The included 5/16" end mill requires approximately 15-20 minutes of continuous milling per receiver. For routers, use a 1/4" collet adapter (not included).