Glock 43/43X Carry Optics Setup Guide

Posted by Desert Cat USA on Oct 17th 2026

Glock 43/43X Carry Optics Setup Guide

The Glock 43 and 43X have become the default carry platform for a lot of everyday carriers. Slim profile, reliable, manageable recoil, and with the right slide, fully optics-ready. Here’s everything you need to build a G43/43X carry optics setup from the ground up.

G43 vs. G43X: What’s the Difference?

The G43 is a single-stack 9mm subcompact with a 3.41-inch barrel and 6+1 capacity. The G43X uses the same slim slide but pairs it with a longer grip that runs 10+1. Both models use identical slide dimensions, Desert Cat slides and barrels for the G43/43X fit both models.

The RMSC / 407K Optic Footprint

The G43/43X uses the RMSC/407K optic cut, a smaller mounting footprint than the RMR cut used on full-size Glock platforms. The RMSC positions the optic lower over the bore axis, which is important for a concealed carry pistol where every millimeter of height matters.

Do not attempt to mount a full-size RMR-footprint optic (Holosun 507C, Trijicon RMR, etc.) on an RMSC-cut slide without an adapter plate. They are different footprints.

Optic Options for the RMSC / 407K Cut

Optic Reticle Key Feature Best For
Holosun 407K 2 MOA dot Solar + battery, lightweight Simplicity, long battery life
Holosun 507K Dot / Circle Dot / 32 MOA circle Multi-Reticle System, Shake Awake Versatility, aiming options
Holosun EPS Carry Dot or Circle Dot Enclosed emitter, fully sealed Harsh conditions, max durability
Shield RMSc 3.5 MOA dot Very compact, low-profile Minimal height, light weight

Complete Slide vs. Stripped Slide for This Build

Start Here: Complete Slide

Desert Cat G43/43X complete slide assemblies arrive fully assembled with barrel, recoil spring assembly, internals, polymer sights, and RMSC cover plate installed. Mount your optic, install the slide on your frame, and you’re done.

For the Custom Build: Stripped Slide

Desert Cat G43/43X stripped slides are milled to the RMSC/407K footprint and accept OEM G43/43X barrels as well as aftermarket barrels built to the same spec. G43/43X barrels are also available separately from Desert Cat.

Holster Considerations

An optic-equipped G43/43X needs a holster cut for the optic. Most major holster makers (Safariland, Dark Star Gear, Tenicor, Vedder) now offer G43/43X models with optic clearance for common RMSC-footprint optics. Confirm your specific optic model is listed as compatible before buying.

Function Check and Carry Prep

After building the slide, run at least 50 rounds of your intended carry ammunition before trusting the setup. Confirm reliable feeding, extraction, and ejection. Verify zero at 10 yards. Confirm the optic doesn’t shift under recoil. Then run another 50.

A carry gun earns its place on your belt.

• G43/43X Complete Slides • G43/43X Stripped Slides • G43/43X Barrels • G43/43X Model Page

Desert Cat USA • desertcatusa.com • Made in Arizona

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