Best Red Dots for a Glock 19: MOS Plates vs an RMR-Cut Slide

Two ways to mount a dot

A pistol red dot bolts into a pocket cut into the top of the slide. On a Glock 19 there are two common ways to get that pocket.

MOS (Modular Optic System): Glock's factory optic-ready slide. It has a cover plate, and you swap that for an adapter plate that matches your optic.
Direct cut: an aftermarket slide milled for one footprint, usually the Trijicon RMR. The optic screws straight into the slide with no plate.

MOS: flexible, a bit taller

MOS works with many optics because you just change plates. That's handy if you aren't sure which dot you want yet.

The trade-off is height and one more joint. The plate raises the dot, which can make co-witnessing with iron sights harder, and the plate screws are one more thing that can loosen. Use the plate made for your exact optic and follow its torque spec.

Direct RMR cut: lower and simpler

A slide cut for the RMR footprint sits the dot lower and has fewer parts in the stack. The catch is that you're locked into that footprint, though RMR is the most common one.

Options in the Glock Studio for a Gen5 G19 include the Brownells RMR Cut Slide (about $229) and the ZEV Z19 Duty RMR Slide (about $299). Slides for Gen3 frames are different, so match the slide to your generation.

Footprints, in plain English

RMR: Trijicon RMR, Trijicon SRO, Holosun 407C and 507C. The most common full-size footprint.
Holosun 509T: uses its own footprint, mounted with an RMR adapter.
ACRO: Aimpoint ACRO and similar enclosed dots. Needs its own plate or cut.
DeltaPoint Pro: Leupold and some SIG Romeo models.
RMSc: small dots for slim pistols like the Glock 43X. Not a full-size Glock 19 footprint.

Red dots that fit a Glock 19

Holosun HS507C X2 (about $233): RMR footprint with a multi-reticle and solar backup. The value pick.
Holosun HS407C X2 (about $245): RMR footprint with a simple dot.
Trijicon RMR Type 2 Adjustable LED (about $589): very tough, common on duty guns.
Holosun HE509T X2 (about $430): enclosed emitter, so rain and lint can't block it. Mounts with an RMR adapter.
Aimpoint ACRO P-2 (about $743): fully enclosed and very durable, but needs an ACRO plate or cut.

Iron sights and holsters

With a dot on the slide, standard sights are hidden below the window. Taller suppressor-height sights let you see them through the glass as a backup. The studio has a few, like the Night Fision suppressor-height set (about $97).

You'll also need a holster cut for an optic. Most modern holsters for the G19 offer an optic-cut version, but check before you buy.

Install tips

Use the screws made for your exact optic and slide or plate. A screw that is too long can bottom out or reach into the slide, and that can cause problems with the striker. Degrease the threads, use the thread locker the maker recommends, and torque to spec. Then test fire and re-check the screws.

Which should you pick

If you already own a MOS G19 and want to try a dot, buy the plate for your optic and start there. If you know you want an RMR-footprint dot for good and want the lowest mount, an RMR-cut slide is the cleaner setup. Try both in the Glock Studio, which flags optics that don't match your slide. Prices are rough street prices and change often, so check current listings before you buy.

Parts in this guide

Holosun HS507C X2

$233 · Red dot

Holosun HS407C X2

$245 · Red dot

Trijicon RMR Type 2 Adjustable LED

$589 · Red dot

Holosun HE509T X2

$430 · Red dot

Aimpoint ACRO P-2

$743 · Red dot

Brownells RMR Cut Slide for Glock 19 Gen5

$229 · Slide

ZEV Technologies Z19 Duty RMR Slide (Gen5)

$299 · Slide

Night Fision Suppressor Height Night Sights

$97 · Sights

Open the Glock builder

Prices are typical and change often. This guide is general information, not legal advice. Suppressors and short-barreled rifles are NFA items; check federal, state and local law.