P80 G150 AR-15 80% Receiver Kit – Gray - polymer 80
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About this product
The Polymer80 P80 G150 AR-15 80% Receiver Kit is a polymer-based incomplete lower receiver requiring machining to complete an AR-15 build. This kit includes the proprietary Phoenix2 jig system for precise milling operations. It serves as a foundational component for custom rifle assembly.
What is the Polymer80 P80 G150 AR-15 80% Receiver Kit used for?
This receiver kit is used for building custom AR-15 rifles from an 80% complete state. The Phoenix2 jig system guides drilling and milling operations to complete the fire control pocket and trigger pin holes. Final assembly requires additional AR-15 components including upper receiver, barrel, and trigger group.
How does the Polymer80 P80 G150 compare to the .308 80% Lower – Billet?
The Polymer80 G150 weighs 9.8 ounces compared to the 15.2-ounce billet aluminum .308 80% Lower. The aluminum version provides superior heat resistance during sustained fire but costs $47 more. Polymer construction offers weight reduction for carbine builds where minimal mass is prioritized.
What does it weigh and what are the dimensions?
The unfinished receiver measures 7.2 inches long, 2.1 inches wide, and weighs 9.8 ounces. Completed weight with installed components typically reaches 1.2-1.4 pounds depending on trigger group selection. These dimensions conform to MIL-SPEC AR-15 pattern requirements for compatibility with standard upper receivers.
Who is this NOT for?
This kit is not for builders lacking milling equipment or jig experience. Completion requires a drill press or CNC mill capable of maintaining ±0.005-inch tolerances. Those seeking finished receivers should consider our Fire/Safe Marked complete lowers instead.
What's in the box?
The kit contains one gray polymer 80% lower receiver, Phoenix2 jig system, three drill bushings, and installation hardware. The jig itself consists of 11 separate components including alignment pins and template plates. No drill bits or milling tools are included—these must be sourced separately per our drill bit guide.
Is the Polymer80 P80 G150 worth it at $79?
At $79, this kit provides cost-effective entry into custom AR building compared to $120+ finished lowers. The included Phoenix2 jig represents a $35 value alone based on separate jig pricing. Budget an additional $40-60 for quality drill bits and end mills to complete the machining process properly.
Specs at a glance
Pros & cons
What works
- Weighs 9.8 oz — 5.4 oz lighter than aluminum billet receivers
- Includes $35 value Phoenix2 jig system with 11 components
- Accepts all MIL-SPEC AR-15 parts after proper machining
Trade-offs
- No drill bits included — adds $40-60 tooling cost
- Polymer material limits sustained fire to 90 rounds between cool-down periods
- Requires drill press or milling machine — not hand tool compatible
Key attributes
| Caliber | 5.56 NATO |
| Material | Polymer |
| Weight | 9.8 oz |
| Finish | Gray |
| Completion | 80% |
| Jig System | Phoenix2 |
| Length | 7.2 in |
| Width | 2.1 in |
Frequently asked questions
- Is it compatible with MIL-SPEC AR-15 parts?
- Yes, the P80 G150 accepts all MIL-SPEC AR-15 components including trigger groups, buffer tubes, and pistol grips. The fire control pocket requires final machining to 0.335-inch width for standard trigger compatibility. Upper receiver fitment follows standard AR-15 takedown pin specifications.
- Does it fit standard AR-15 jigs?
- No, this receiver requires the proprietary Phoenix2 jig system included in the kit. The jig uses three alignment points unique to Polymer80's design. Attempting to use universal AR-15 jigs may result in misaligned trigger pin holes exceeding 0.003-inch tolerance.
- How long does machining take?
- Completion typically requires 45-60 minutes with proper equipment including a drill press and end mill. First-time builders should allocate 2 hours for setup and verification. The process involves 3 drilling operations and 2 milling passes at recommended 1200 RPM spindle speed.
- Does this work with aftermarket triggers?
- Yes, once machined to completion, the receiver accepts aftermarket triggers from Geissele, Timney, and other MIL-SPEC compatible units. The fire control pocket must be milled to 0.335-inch width with 0.154-inch pin holes. Verify trigger group dimensions before final milling depth adjustment.