If you're rocking a Glock MOS (Modular Optic System), adding a Holosun red dot sight could be just the upgrade you need.
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Glock MOS Compatibility
Think of Glock MOS Modular Optic System allows you to snap on red dot sights with minimal fuss.
Gen 4 MOS - The MOS feature was introduced late in Gen4; for example, G17/G19 Gen4 MOS variants appeared around 2016.
Gen 5 MOS - The same as Gen 4 in terms of MOS
Slimline MOS - Glock 43 MOS does not include multiple plates for slimline models; the slide is factory-cut to accept RMSc-pattern optics directly.
Glock MOS pistols include a set of four numbered adapter plates (plus a “Plate 00” cover that fills the cut when no optic is attached). Each plate is a thin metal interface that matches the slide’s optic cut on one side and a specific optic footprint on the other.
- Plate 00 - Blank cover (protects the slide cut when no optic is mounted)
- Plate 01 - Docter/Noblex footprint – e.g. Docter Sight III, Meopta MeoRed, Insight MRDS, EOTech MRDS, Burris FastFire series, Vortex Venom/Viper
- Plate 02 - Trijicon RMR footprint – e.g. Trijicon RMR/SRO, Holosun 407C/507C/508T, Ameriglo Haven
- Plate 03 - C-More STS footprint – e.g. C-MORE STS/RTS, Sig Sauer Romeo3 Max/XL, Vortex Razor reflex
- Plate 04 - Leupold DeltaPoint Pro footprint – e.g. Leupold Deltapoint Pro, EOTech EFLX (uses DPP footprint), Sig Sauer Romeo1**
Key Selling Points of Holosun Red Dot Sights
- Battery & Solar Life: With advanced LED tech offering up to 50,000 hours of battery life and some solar-powered models, these sights are about longevity.
- Side loading tray: No sight removal when swapping battery
- Tough as Nails: Built with IP67 waterproof certifications, these sights tough it out against the elements and kickback.
- Reticle Razzle-dazzle: The Multi-Reticle System lets you switch things up whether you're gunning with a 2 MOA dot, a 32 MOA circle, or both for a little customization flair.
Popular Holosun Red Dots for Glock MOS
- Holosun 507C: Offers a 2 MOA dot and 32 MOA circle. It's flexible for almost any task.
- Holosun SCS MOS: Specifically crafted for Glock MOS, it fits the slide with no adapter needed—totally streamlined.
- Holosun 509T: Rocks an enclosed build to guard against debris and impacts.
Installation Guide
The Glock MOS plates rely on the two screws and the machined fit; they do not have additional recoil lugs or dowels interfacing into the slide (unlike some newer systems). This means the shear forces of recoil are borne largely by the screws and friction.
Over time, this can stress the screws. (By contrast, some other platforms or aftermarket plates add steel pins or lugs that take pressure off the screws
Given the concerns with OEM plates, numerous aftermarket manufacturers offer replacement MOS plates that claim to improve durability, fit, and features. We will examine three prominent brands – C&H Precision (CHPWS), Forward Controls Design (FCD), and others (miscellaneous third-party options)
Step-by-Step Mounting Process
- Prep Your Pistol: Safety first—make sure it’s unloaded before removing the MOS cover plate.
- Select an Adapter Plate: Pick the right one for Holosun sights, but if you have the SCS MOS, skip the plate.
- Secure the Plate: Tighten up those screws with a hex wrench and apply some thread locker for extra security.
- Install the Holosun Sight: Make sure it's on straight and tight.
- Verify Fitment: Double-check everything’s secure and functioning well.
- Always use torque wrench to tighten between 10 to 12 inch pounds on each screw
- Glock pistols always have one screw longer one the left side than the right side.
Frequently Asked Questions
What Holosun model is best for my Glock MOS?
The Holosun SCS MOS is specifically designed for Glock MOS pistols, offering a streamlined fit without the need for adapter plates. However, models like the Holosun 507C and 509T are also popular choices depending on your preferences.
For 509T, you need an aftermarket adapter
Do I need an adapter plate to mount a Holosun sight on my Glock MOS?
Most Holosun sights will require the appropriate adapter plate that comes with your Glock MOS. However, the Holosun SCS MOS is designed to fit directly onto the slide without any adapter.
Are Holosun sights durable enough for heavy use?
Absolutely. Holosun sights are built with rugged materials and are rated IP67 waterproof for open emitter ones like the Holosun 507C. However, the durability is also depended on how tight the optic can be wedged inside the slide cutout so not all stress is exerted on the screws.