Glock 20 Gen 4 OEM Frame

Upgrade or rebuild your Glock 20 with a factory-spec Glock 20 Gen 4 OEM Frame — the large-frame lower receiver engineered to manage the power of 10mm Auto while delivering Glock’s proven durability, ergonomics, and reliability. This frame accepts proper Glock 20 Gen-4 pattern components, making it ideal for duty, defense, hunting, or replacement builds.

Product Description | Specs for Glock 20 Gen 4 OEM Frame

The Glock 20 Gen 4 Frame is molded from Glock’s high-strength polymer blend and designed to withstand the recoil and pressures of 10mm Auto. Gen-4 enhancements include interchangeable backstrap capability, improved grip texture, and a reversible magazine release. Reinforced steel rail inserts, Gen-4 pin geometry, and large-frame dimensions ensure consistent lockup and long service life with Glock 20 Gen-4 slide assemblies.

What’s Included For Complete OEM Frame

A complete OEM Glock 20 Gen 4 frame assembly normally includes:

• Serialized Glock 20 Gen 4 polymer frame
• Glock Gen-4 lower parts kit (LPK), including:
  • Trigger housing with ejector
  • Slide stop lever
  • Trigger with trigger bar
  • Connector
  • Magazine catch and spring (reversible)
  • Trigger pin, locking block pin, and housing pin
• Locking block (Gen-4 large-frame specific)
• Interchangeable backstrap set (size dependent by supplier)
• Front accessory rail on the dust cover

(Actual included parts vary by supplier and build kit; verify specifics before purchase.)

What’s Included For Stripped OEM Frame (No LPK)

A stripped OEM frame provides the bare serialized polymer lower:

• Glock 20 Gen 4 polymer frame only
• Factory-molded steel rail inserts
• Pin holes and bosses ready for Gen-4 LPK installation

Stripped frames do not include any internal parts, pins, locking block, or control components.

Specifications

• Model: Glock 20 Gen 4 OEM Frame
• Material: High-strength polymer with steel rail inserts
• Finish: Black matte polymer
• Compatible Caliber: 10mm Auto (when complete with slide/barrel assembly)
• Frame Size: Full-size large frame (G20 pattern)
• Generation: Gen 4
• Accessory Rail: Standard Glock universal rail

How to Install a Glock 20 Gen 4 OEM Frame

Install the Lower Parts Kit (LPK)

• Ensure safety: confirm all components are unloaded and clear
• Install trigger housing, trigger bar, and connector per OEM layout
• Install slide stop lever, magazine catch, and springs
• Install pins to retain internal components
• Function-check trigger, reset, and magazine release

Attach the Slide Assembly

• Place the Glock 20 Gen-4 slide assembly onto the frame rails
• Pull the slide fully rearward then release to seat
• Rack the slide several times to verify smooth travel
• Perform a dry-function check before live fire

(Refer to Glock’s official Gen-4 schematics for part orientation and order.)

How To Disassemble A Glock 20 Gen 4 OEM Frame

• Remove the slide assembly and store it separately (frame alone cannot function)
• Remove all magazines and store them separately
• Use a cable lock or trigger lock through the frame/magwell
• Store ammunition separately from the frame
• Lock the frame in a secure container or gun safe
• For permanent disabling: contact a licensed gunsmith or FFL (do not modify it yourself)

Compatibility

• Fits: Glock 20 Gen-4 slides and upper assemblies
• Parts Compatibility: Use Gen-4 large-frame (10mm/.45) lower parts only
• Magazines: Glock 20 (10mm) magazines
• Gen Mix: Not compatible with Gen-3 or Gen-5 internals or frames without modification

What’s The Glock 20 Gen 4 OEM Frame Made Of?

The Glock 20 Gen 4 OEM Frame uses Glock’s proprietary polymer blend for impact resistance and durability while minimizing weight. Embedded steel rails reinforce high-stress contact points, and Gen-4 geometry supports reliable lockup and long-term performance under heavy recoil.

Customization Options

• Grip Size: Interchangeable backstraps to adjust grip circumference
• Grip Texture: Professional stippling or texture enhancements
• Controls: Extended or enhanced Gen-4 compatible slide stop levers and magazine releases
• Magwells: Compatible flared magwells for improved reload speed

Note: Modifications may affect warranty or serviceability; consult a qualified armorer.

FAQs

Q: Does this frame include internal parts?
Complete kits include Gen-4 lower parts; stripped frames do not. Always verify what’s included before purchase.

Q: Can I use a Glock 21 slide on this frame?
No. Glock 20 frames are designed specifically for 10mm Auto slide assemblies.

Q: Are Gen-3 or Gen-5 parts compatible?
No. The Glock 20 Gen-4 frame requires Gen-4 large-frame components.

Q: Will aftermarket parts affect reliability?
OEM-spec parts provide the highest reliability; thoroughly test any aftermarket components before use.

DISCLAIMER

OEMGlockParts.com provides aftermarket and compatible parts and components for GLOCK pistols. We operate independently and do not represent, endorse or have any connection with GLOCK, Inc. or GLOCK Ges.m.b.H.

GLOCK, Inc. and GLOCK Ges.m.b.H own the trademark “GLOCK” and other related marks. We mention “GLOCK” only to identify parts and products that fit or work with GLOCK pistols.