High-Capacity 26-Round Magazine for Glock .45 ACP - Black (Made in USA)

The KCI USA High-Capacity 26-Round Magazine for Glock .45 ACP doubles your standard factory magazine capacity, letting you spend more time shooting and less time reloading at the range or during competition drills. Built domestically and engineered to match factory specifications, this magazine delivers the reliability Glock shooters expect without sacrificing durability or function—whether you're running tactical drills, prepping for competition, or just maximizing trigger time.

Like any premium high-capacity magazine, the KCI 26-rounder will perform best after a brief break-in period. The tempered chrome silicon spring needs a few load/unload cycles to settle and accept its full capacity comfortably. Start by loading it to half capacity and letting it sit overnight; this eases the spring in and makes future loading smoother. After that conditioning, you'll get reliable feeding and smooth round stacking session after session.

Construction mirrors the factory design: a durable polymer body reinforced with a stainless steel sleeve, paired with a polymer follower that keeps rounds moving reliably under pressure. The baseplate is tool-free to remove for cleaning, and witness holes let you see your round count at a glance. The magazine accepts standard Glock 21 accessories, so you can customize fit and function to match your setup. Yes, the extended capacity means it protrudes further from the magwell than a standard Glock 21 magazine—a practical trade-off for shooters who prioritize round count over a flush fit.

Key Features

• 26-round capacity—twice the standard factory Glock 21 magazine
• Made in USA with polymer body and stainless steel reinforcing sleeve
• Tempered chrome silicon spring for smooth, reliable feeding
• Witness holes for quick round-count visibility
• Tool-free removable baseplate for easy cleaning
• Compatible with standard Glock 21 magazine accessories
• Built to factory-spec tolerances and durability

Specifications

Frequently Asked Questions

Will this magazine fit my Glock 21?

Yes. The KCI 26-round magazine is designed for the Glock 21 and is built to factory specifications for reliable fit and function. It will also accept standard Glock 21 magazine accessories.

How long does break-in take, and do I have to do it?

The spring benefits from a few load/unload cycles before it fully settles into accepting all 26 rounds comfortably. To speed this up, load the magazine to half capacity and let it sit overnight. After that conditioning, it will load and feed smoothly. Skipping break-in may make initial loading feel stiff, but the magazine will still function—the spring just needs time to relax.

What's the difference between this and my factory Glock 21 magazine?

This KCI magazine holds 26 rounds instead of the standard capacity, doubling your ammunition count per magazine. The trade-off is that it protrudes further from the magwell due to the extra height needed for those additional rounds. The construction and materials are the same as factory magazines.

Can I use magazine accessories with this?

Yes. The KCI 26-round magazine is compatible with accessories designed for standard Glock 21 magazines, so you can add baseplates, extensions, or other aftermarket parts as needed.