Description

Polymer80 PF940CL 80% Long-Slide Compact Frame — Competition-Ready Build Platform

The Polymer80 PF940CL 80% Compact Long-Slide Frame and Jig Kit is the builder’s solution for achieving competition-grade performance without the full-size grip profile. This frame blank accepts Glock 19L and Glock 34 compatible slide assemblies while maintaining the compact G19-size grip — a combination no factory pistol currently offers.

California Gun Shop carries this kit for serious builders who want maximum performance from their custom builds. Whether you’re building for USPSA competition, personal defense with extra barrel length, or simply because you want a pistol exactly the way you want it, the PF940CL is the frame to start with. Browse our Polymer80 PF940v2 frame only and PF940SC subcompact kits for comparison.

Why the Long-Slide Compact Format?

Competition shooters have known for decades that a longer sight radius and longer barrel improve accuracy and muzzle velocity. The Glock 34 has been a USPSA Production division staple for years because of exactly this. But it comes with a long grip that’s harder to conceal and some shooters find less ergonomic than the compact profile.

The PF940CL solves this by extending only the front of the frame — the rail section and dust cover — to accept the 5.31″ slide while leaving the grip at compact dimensions. The result is a pistol that shoots like a G34 and carries (when needed) like a G19. No factory solution exists for this configuration, which is precisely what makes the PF940CL so compelling for custom builders.

Also available in our 80% Frames section: Polymer80 PF940Cv1 compact kits and PF940v2 full-size kits. Check our complete 80% Lower selection for all available options.

Kit Contents

• One PF940CL 80% frame blank (color options: Black, FDE, OD Green, Gray)
• Billet 6061 aluminum top and bottom jig plates
• Pre-sized drill bits for the trigger cavity
• End mill bits for rail section
• Complete hardware fastener set
• Step-by-step machining instruction booklet

Technical Specifications

Specification	Detail
Brand	Polymer80
Model	PF940CL
Completion State	80% (requires machining)
Compatible Platform	Glock 19L / Glock 34 (Gen 3)
Grip Profile	G19 Compact Width
Slide Length	5.31″ (Glock 34 format)
Caliber Options	9mm, .40 S&W (barrel dependent)
Frame Material	Reinforced polymer composite
Jig Material	Billet aluminum 6061
Front Rail	Extended for G34-length slide
Accessory Rail	Integrated Picatinny rail
Tooling Included	Yes — drill bits + end mills
Made In	USA

Build Component Requirements

After completing the 80% machining, you’ll need the following to finish your pistol:

• Glock 34 / 19L compatible slide (5.31″ — bare or complete assembly)
• 5.31″ G34-compatible barrel in 9mm or .40 S&W
• Glock Gen 3 compact lower parts kit
• Polymer80 PF940 Rear Rail Module (RRM)
• Compact-compatible locking block
• Glock 17 or 19 compatible magazines
• Front and rear sights for the slide

We carry a wide selection of compatible slides and accessories. Check out our Complete G17 Slide for P80 PF940V2/PFS9 for a ready-to-install upper assembly option. Also see our complete 80% Frames inventory.

Pros and Cons

Pros:

• Only long-slide compact frame platform on the market — unique build
• Complete jig kit included — all bits and hardware provided
• G34 aftermarket is enormous — unlimited slide and barrel options
• Proven Polymer80 engineering and quality
• US manufactured reinforced polymer frame blank
• Competition-legal configuration for most USPSA/IDPA divisions

Cons:

• Requires machining to complete — not a ready-to-build drop-in kit
• Best results from a drill press rather than handheld drill
• Upper assembly components sold separately
• California legal compliance varies by local jurisdiction (see below)

⚠️ California Buyers — Important Legal Notice

California law significantly restricts the manufacture and possession of unserialized firearms. Under California Penal Code 29180-29184 (AB 1621 and subsequent amendments), California residents who manufacture or assemble a firearm from an 80% lower or frame must:

• Apply for a Department of Justice-issued serial number BEFORE beginning machining
• Engrave or permanently affix the assigned serial number to the frame before assembly
• Ensure the firearm meets all California handgun roster requirements where applicable
• Not transfer or sell a homemade serialized firearm to another person

Purchasing an 80% frame blank that is not yet a firearm may still be legal in California, but machining and completing it without prior DOJ serialization is illegal under current California law. This listing is provided for informational purposes. California Gun Shop strongly recommends consulting a California-licensed firearms attorney before purchasing or completing any 80% firearm frame in California.

Frequently Asked Questions

Q: Is the Polymer80 PF940CL legal to purchase in California?

A: Purchasing an 80% frame blank in its unfinished state occupies a legal gray area in California. California’s AB 1621 and related statutes regulate the manufacture (completion) of unserialized firearms, not necessarily the purchase of unfinished blanks. However, completing the frame — the actual machining — requires obtaining a DOJ serial number first. We strongly recommend consulting a California firearms attorney before ordering.

Q: What slide length does the PF940CL accommodate?

A: The PF940CL is specifically designed for Glock 34 / 19L format slides measuring 5.31″ in length. This is the long-slide dimension — longer than the standard G19 (4.02″) and slightly longer than the G17 (4.49″). Do not attempt to install shorter slides as the front rail section is configured for the extended length.

Q: Can I build this with aftermarket components instead of OEM Glock parts?

A: Yes, and many builders prefer it. The aftermarket for Glock-compatible components is enormous. Brands like Agency Arms, Zev Technologies, Lone Wolf, and Strike Industries all make G34/19L compatible slides, barrels, and triggers. The advantage of custom builds is precisely this — you can mix and match premium components to build a pistol tuned exactly to your preferences.

Q: How difficult is the machining process?

A: Polymer80 rates the PF940CL as intermediate difficulty. The jig provides clear positive-stop guides for all drilling operations, making the process straightforward for those with basic tool experience. A drill press, standard vise, and the included bits are sufficient. If you’ve never used a drill press before, consider watching Polymer80’s official build video series before starting.

Q: Does the PF940CL require a separate locking block?

A: Yes. A Glock Gen 3 compact-compatible locking block is required. This component seats in the locking block channel of the completed frame and is the bearing surface for the barrel during cycling. It should be sourced as part of your Gen 3 compact lower parts kit or purchased separately. Several aftermarket manufacturers offer upgraded steel locking blocks for enhanced durability.