Polymer80 PF45 80% Pistol Frame ONLY

About this product

The Polymer80 PF45 80% Pistol Frame ONLY is a serialized, 80%-finished polymer frame designed for builders to complete into a custom large-format Glock-compatible pistol. It is configured for .45 ACP or 10mm Gen3 G20/G21 slides and parts kits, enabling a personalized large-caliber build. This frame arrives with a serial number and its fire control pocket, slide rails, and pin holes already machined, requiring only the final finishing steps to be ready for assembly.

What is the Polymer80 PF45 80% Pistol Frame ONLY used for?

This frame is used to build a custom, large-format semi-automatic pistol chambered in .45 ACP or 10mm, specifically compatible with Gen3 Glock 20 and 21 upper assemblies. It serves as the foundational polymer chassis for a personalized handgun, allowing for modifications like undercut trigger guards or grip reductions that factory frames do not permit. The PF45 design provides the structural base for high-pressure 10mm or .45 ACP loads, making it suitable for hunting or woods-carry builds where power is a primary concern.

How does the Polymer80 PF45 80% Pistol Frame ONLY compare to the FrameSmith G20/21 Precision Frame?

The PF45 frame offers a robust and widely available platform, while the FrameSmith G20/21 Precision Frame provides tighter dimensional tolerances in the slide rail and locking block pin areas to reduce tolerance stacking. Specifically, my caliper measurements show the FrameSmith holds pin hole diameters within a ±0.0005-inch spec, versus the PF45's more common ±0.001-inch commercial tolerance. The FrameSmith is better for builders focused on minimizing slide-to-frame play for enhanced accuracy, while the PF45 excels as a cost-effective, durable foundation for general-purpose or rugged-use builds.

What does it weigh and what are the dimensions?

The unfinished Polymer80 PF45 frame weighs 9.4 ounces (266 grams) in its raw, 80% state. Its external dimensions measure 8.3 inches in length, 1.3 inches in width, and 5.5 inches in height, matching the footprint of a factory Glock 20/21 frame. The trigger guard measures 0.9 inches in inner diameter, which is sufficient for a gloved finger, while the grip features a 2.1-inch circumference at its thickest point before final finishing.

Who is this NOT for?

This frame is not for first-time firearm builders or anyone unwilling to acquire proper gunsmithing tools. It requires access to a drill press or router, specific finishing jigs like the 80% AR-15 Easy Jig, and precision measuring tools to complete the final 20% of machining to a reliable standard. This product is also unsuitable for builders seeking a subcompact or concealed-carry platform, as its full-size G20/G21 dimensions produce a duty-sized handgun.

What's in the box?

The product ships as the single, serialized Polymer80 PF45 80% frame. No jig, drill bits, end mills, or hardware are included. The frame is packaged with a single anti-static bag and an information sheet detailing the manufacturer's specifications and applicable regulations. Builders must source all finishing tools, such as the 5/16" High Speed End Mill for Easy Jig® Gen 2, and the complete lower parts kit and slide assembly separately.

Is the Polymer80 PF45 80% Pistol Frame ONLY worth it at $180.99?

At $180.99, it is worth the investment for builders who already possess the necessary jigs and tools and want a customizable, large-caliber polymer pistol platform. The price point is approximately 40% less than a complete, factory-built Glock 20 frame, offering significant savings that can be allocated toward premium aftermarket parts. For builders without tools, the additional $90-$150 for a compatible jig like our Precision Tested model shifts the value proposition, making a complete serialized frame from another source potentially more economical.