(Disclaimer: This is a commercial website with products and services to sell.)


Here is a nice Cliff's Notes kind of summary for some current RDS mounting options, presented by 3CR Tactical.

There's more information in the webpage beyond these excerpts, with charts and references to handgun models and RDS's.

Hope you find it helpful, as did I.



https://3crtactical.com/blog/p...r-rmsc-acro-dpp-eps/


(Disclaimer: This is a commercial website with products and services to sell.)

Pistol Red Dot Footprints: RMR, RMSc, ACRO, DPP, EPS
Posted by 3CR Tactical on 14th May 2026



"Slide cut and optic footprint are not the same thing — and getting them mixed up is the single biggest mistake we see at checkout. A footprint is the mounting pattern on the bottom of an optic. A slide cut is the milled recess on top of the slide that has to match it. If the screw holes and recoil lugs don't line up, the optic doesn't sit flat, and nothing you torque it to will make it shoot zero. This guide maps every major pistol red dot footprint in the 3CR Tactical catalog to the optics, slides, and adapter plates that go with it."

"What a Footprint Actually Is
A footprint is a standardized hole pattern and recoil-lug arrangement on the underside of a reflex sight. Optic manufacturers settle on a pattern, slide makers cut to match, and from then on every optic and every slide that share that pattern interchange — or should. The footprints below cover roughly 95% of what gets sold on Glock-pattern, Sig, and Smith & Wesson slides today.

Two things make up a footprint:

Screw pattern — center-to-center spacing of the mounting screws, plus thread size (typically 6-32 or M4)
Recoil lugs — small posts or pins on the underside of the optic that key into matching cuts in the slide; these absorb slide cycle force so the screws aren't doing it alone"