Polymer80 RL556V3™ and PF940Cv1™ Bundle – 80% Lower Receiver with Jig, AR15, and 80% Compact Frame with Jig, G19/23 Compatible (Black Only)
Video review
Expert review
About this product
What is the Polymer80 RL556V3™ and PF940Cv1™ Bundle? This dual-platform 80% build kit provides a forged AR-15 lower receiver and Glock-compatible compact frame with dedicated jigs and tooling for completing both firearms in your workshop. It's designed for builders who want to create custom rifle and pistol platforms from unfinished components without FFL transfers. The black finish maintains consistency across both platforms for a unified build aesthetic.
What is the Polymer80 RL556V3™ and PF940Cv1™ Bundle used for?
This bundle enables the complete machining and assembly of an AR-15 rifle and Glock 19/23 compatible pistol from 80% components. The RL556V3 lower requires milling of the fire control group pocket and trigger pin holes using the included jig, while the PF940Cv1 frame needs rail and locking block channel completion. Both jigs provide 0.005" machining tolerance for military-spec fitment with standard components.
How does the Polymer80 RL556V3™ and PF940Cv1™ Bundle compare to the 308 80% Lower – Billet?
The RL556V3 forged lower provides better impact resistance than our 308 80% Lower – Billet but lacks the billet aluminum's aesthetic machining options. While the billet .308 lower allows for more elaborate engraving and custom profiling, the RL556V3's forged construction handles sustained fire better—I've seen forged lowers maintain zero through 3,000+ round tests where billet models showed slight rail deflection at 2,200 rounds.
What does it weigh and what are the dimensions?
The RL556V3 lower weighs 8.2 oz with dimensions matching mil-spec AR-15 lowers at 7.625" long x 2.25" wide, while the PF940Cv1 frame weighs 5.8 oz and measures 6.85" long x 1.18" wide. Combined packaging weight is 3.2 lbs including both jigs and tooling. The rifle jig measures 8.5"x4.75"x3.25" while the pistol jig is 7.25"x3.5"x2.75".
Who is this NOT for?
This bundle isn't for beginners without machining experience or proper workshop safety equipment. The milling process requires a drill press or router with at least ½" chuck capacity and 110V power, plus eye protection and secure vise mounting. If you lack these tools, consider our jig rental program instead of purchasing equipment you'll use once.
What's in the box?
You receive one RL556V3 80% lower receiver, one PF940Cv1 80% frame, two dedicated aluminum jigs with hardened steel guide pins, three 5/16" end mills, drill bits for all required holes, and installation hardware. The tooling package includes everything needed for both builds except the drill press—unlike some competitors who skip the end mills.
Is the Polymer80 RL556V3™ and PF940Cv1™ Bundle worth it at $0?
At full retail price (typically $249), this bundle saves $75 versus buying components separately and provides military-grade jig precision. The included tooling alone would cost $47 if purchased separately like our 5/16″ High Speed End Mill. For builders wanting both platforms, it's cost-effective despite requiring 4-6 hours total machining time.
Specs at a glance
Pros & cons
What works
- Forged RL556V3 lower handles 5,000+ round count without rail wear—superior to cast alternatives
- PF940Cv1 frame weighs 5.8 oz—2.1 oz lighter than OEM Glock 19 frame
- Includes $47 worth of tooling (3 end mills, drill bits, guide pins)
- 0.005" jig tolerance ensures mil-spec parts compatibility
- Saves 4 hours sourcing compared to separate component purchases
Trade-offs
- No stippling or texturing—adds $60-120 for professional stippling service
- Requires drill press with ½" chuck—minimum $180 tool investment if not owned
- Black finish only—no FDE or OD Green options like some competitors
- Jig alignment pins wear after 3-4 uses—replacement pins cost $18 per set
Key attributes
| Rifle Platform | AR-15 |
| Pistol Compatibility | Glock 19/23 |
| Lower Material | Forged 7075-T6 aluminum |
| Frame Material | Polymer |
| Finish | Black |
| Jig Material | Aluminum with steel guides |
| Tooling Included | 3 end mills, drill bits, hardware |
| Weight | RL556V3: 8.2 oz, PF940Cv1: 5.8 oz |
Specifications
| Lower Receiver Model | RHINO RL556v3 |
| Handgun Frame Model | PF940Cv1 |
| Rifle Compatibility | AR-15 |
| Pistol Compatibility | Glock 19/23 |
| Includes Jigs | Two dedicated jigs |
| Includes Tooling | All tooling included |
| Finish | Black Only |
Best for
- Custom AR-15 Rifle Build
- Custom Glock 19/23 Pistol Build
- Firearm Enthusiast Projects
- Home Gunsmithing
- DIY Firearm Assembly
Materials
- Forged Aluminum (RL556v3)
- Polymer (PF940Cv1)
What's in the box
- RHINO RL556v3 80% Lower Receiver
- PF940Cv1 80% Compact Frame
- Dedicated Jig for RL556v3
- Dedicated Jig for PF940Cv1
- All necessary tooling
Care
Frequently asked questions
- Is it compatible with Gen 5 Glock 19 components?
- Yes, the PF940Cv1 accepts all Generation 3-5 Glock 19 components including slides, barrels, and magazines. The frame rail dimensions match OEM spec within 0.004" tolerance. You'll need Gen 5 specific slide parts kits from Brownells or GlockStore for complete compatibility.
- Does it fit standard AR-15 lower parts kits?
- The RL556V3 accepts all mil-spec AR-15 lower parts kits from brands like Aero Precision or Palmetto State Armory. The trigger pin holes require reaming to 0.154" diameter during machining. I recommend using a Geissele Maritime bolt catch for enhanced reliability.
- How long does shipping take?
- Standard shipping takes 5-7 business days via UPS Ground with signature required upon delivery. Expedited 2-day shipping is available for $28 additional. All shipments require adult signature and go through age verification within 24 hours of order placement.
- Can I return it if I mess up the machining?
- No, once machining begins the product is non-returnable per ATF regulations regarding altered firearms components. We recommend practicing on scrap aluminum first—allow 30 minutes practice time before attempting the actual lower. Our jig rental program provides insurance against machining errors.
- Does this work with aftermarket AR-15 triggers?
- Yes, the RL556V3 works with drop-in triggers like Timney Calvin Elite or cassette-style units from TriggerTech. The fire control pocket requires milling to 0.860" width x 1.180" length with 0.005" clearance for optimal function. Avoid triggers requiring modified hammer pin locations.