You went looking for a red dot for your pistol and found out the slide has nowhere to put one. This is the most common dead end in pistol optics, and most of the advice around it skips straight to “get it milled” without telling you what the makers themselves say about any of it.
So here is the honest version, built only from what gun makers and milling services publish about their own products. What “optics-ready” means, how to tell which kind of slide you own, which of three situations you are actually in, and what each way forward costs you.
What “optics-ready” actually means
An optics-ready pistol has a pocket machined into the top of the slide, behind the ejection port, where the rear portion of the slide has been cut away to a specific pattern of screw holes and locating features. That pattern is called a footprint, and it decides which optics can bolt on. Our footprint guide maps the patterns you will meet.
Makers do this two ways. Some mill the slide for one footprint directly, so matching optics drop in with nothing in between. SAR USA takes that approach on the SAR9 SOCOM Compact: its product page says the slide is “Milled with an RMSc footprint to accept leading micro red dots” and lists the optic cut as RMSc in the spec table.
Others mill a generic pocket and ship a kit of adapter plates, so one slide can take several optic families. Glock’s optic-mounting page describes its standard version: “GLOCK pistol models in standard MOS configuration now come with a single MOS adapter plate. The adapter plate included will fit the following: Trijicon, Ameriglo, and Holosun (except 509).”
The important part for you: both of those are things the slide has to be born with. There is no plate, riser or adapter that adds a cut to a slide that does not have one. If the pocket is not there, the mounting surface is not there either.
How to tell whether your slide has a cut
Three checks, quickest first.
- Look at the slide. Behind the ejection port, a cut slide has a rectangular recess. On a factory optics-ready pistol it is almost always covered by a small plate held down by two screws, level with the top of the slide. Pop that plate off and you are looking at the cut. If the rear sight sits in its dovetail with solid steel in front of it and no cover plate anywhere, you have no cut.
- Check the box. An optics-ready pistol ships with adapter plates or a cut-specific cover plate, plus a manual that names which optics each plate fits. No plates in the box is a strong signal.
- Check your model on the maker’s site. This is the one that settles it, because makers sell the cut as a different product. Glock’s page for the base Glock 26 V says nothing about an optic cut, while the Glock 26 V MOS is its own catalog entry. SIG’s own operator’s manual for the P938 describes “drift adjustable fixed sights” and lists the sights as “Contrast or SIGLITE Night Sights”, with no mention of an optic anywhere in the document.
Which of three situations you are in
The guns people ask about split cleanly into three groups, and the group decides your options.
1. The whole line already ships cut. Nothing to solve. Springfield’s XD-M Elite 4.5” OSP 10mm is sold only as an optics-cut model, Smith & Wesson’s M&P 5.7 page states “Featuring an optic-cut slide, you can mount most micro red dots”, the SAR9 SOCOM Compact is milled for RMSc, Ruger’s MAX-9 carries the optic pattern “JPoint and Shield RMSc” in its own model data, and Canik’s METE SFT page states the “Optics-ready slide accept the the [sic] Trijicon RMR/RMRcc and Shield RMS/RMSc footprint micro optics”. If your gun is one of these, go straight to matching a footprint.
2. Your model has no cut, but the maker sells a cut version of the same gun. This is the situation most buyers are in and the one most worth knowing about, because buying the right model is cheaper and simpler than modifying the wrong one.
| Your pistol | The maker’s cut version |
|---|---|
| Glock 26 V | Glock 26 V MOS, a separate catalog model, with no retail buy link on its page |
| Taurus G3 with steel sights (other G3 SKUs, including the T.O.R.O., differ) | Taurus G3 T.O.R.O., whose slides “feature a factory optic cut” with an interchangeable plate system |
| CZ P-10 C, fixed rear sight | CZ P-10 C OR, listed as its own variant |
| Glock 19 Gen3 | Not a Gen3 option. Glock’s current catalog answer for a G19 owner is the G19 Gen5 MOS, a different generation of gun |
3. No cut, and no cut version exists. The Glock 42 and the Glock 29 are here: neither has an optic cut, and Glock’s catalog lists no MOS version of either. The Walther P99 is here for a different reason, in that Walther no longer lists the pistol at all, so there is no factory optics-ready P99 and no current maker documentation to check. For this group the only two paths are aftermarket.
The paths open to an uncut slide
Buy the maker’s cut version. Where one exists, this is the only path that leaves you with a factory gun, a factory warranty and a mounting surface the maker designed and supports. The trade is that you are buying a pistol, not a part. Our mounting walkthrough covers what happens after.
A mount that replaces the rear sight. These clamp or screw into the rear sight dovetail and present an optic footprint above it, so the slide is never cut. EGW makes them for common pistols and publishes each mount’s dimensions, hardware and which optics it fits. What EGW does not publish on those pages is how high the optic ends up sitting or whether anything co-witnesses with it, and we are not going to invent numbers for you. Measure, and ask EGW about your specific mount before you buy.
Milling your own slide. A gunsmithing service cuts the pocket into the slide you already own, for the footprint you choose. C&H Precision mills for Glock, SIG, the Springfield Hellcat, Taurus G3 variants, M&P, HK, CZ, the Walther PDP and Defense line, SAR9, Stoeger STR-9, Shadow Systems and 1911/2011 pistols, and it publishes a turnaround commitment: “We guarantee shipment of your optic-cut slide milling order within 4 weeks of payment. If we miss this deadline, your next milling service is free.” That guarantee has limits C&H states plainly: “This guarantee applies only to our optic-cut service. The following modifications void the 4-week guarantee: Serrations (any kind), windows, pockets, or corner chamfers, or custom paint and Black Nitride.”
Prices for milling are quoted per pistol and per configuration on the service’s own order page, so check yours there rather than trusting a number from a forum.
What each path gives up
Only two of these trade-offs have a maker or a service standing behind them, so those are the only two stated here.
Your maker’s warranty position on modification. Every maker we checked publishes an exclusion, and the wording is worth reading before a slide leaves your hands.
- Glock: the warranty “may be voided” if “Your GLOCK pistol or any of its parts are altered or modified from their original state” (Glock warranty, as published).
- Smith & Wesson excludes “unauthorized adjustments or modifications made or attempted by anyone other than a qualified gunsmith following Smith & Wesson authorized procedures” (S&W warranty).
- CZ-USA: “Modifications, tuning, or alterations performed by any third party, including CZ Custom and Cajun Gun Works, are not covered under the CZ-USA warranty and may void certain aspects of coverage.” (CZ warranty)
- Taurus lists “unauthorized adjustments or modifications” among the causes it is not responsible for (Taurus limited lifetime warranty).
- SIG Sauer: the limited warranty “does not apply … if unauthorized repair or any alteration, including of a cosmetic nature, has been performed on the product” (SIG Infinite Guarantee).
Note what none of them says: that a milled slide is unsafe, or that the gun stops working, or what the maker will actually do when your pistol comes back for something unrelated. Those are conversations with the maker, not facts we can look up. Buying the cut version instead is the one path that raises none of this.
Your rear sight, if you use a dovetail mount. A mount that occupies the rear sight dovetail is sitting where the rear sight sat. Any sighting arrangement above it is a question for the mount’s maker and your specific optic, and EGW does not publish a co-witness statement on the mount pages we could read.
The third thing people ask about, whether milling weakens the slide, we are leaving alone. No maker or milling service we fetched publishes a statement about it, and an answer assembled from opinion would be worth less than no answer.
What to do next
- Settle which situation you are in, using the three checks above. Your own maker’s product page for your exact model is the authority.
- If a cut version of your gun exists, price it against milling plus an optic before you decide. The fit pages for the Glock 26 V MOS, the CZ P-10 C OR and the Glock 19 Gen5 MOS list what each one takes. Check availability too: Glock’s own page for the 26 V MOS carries no retail buy link and does not state retail availability, so confirm with a dealer before you plan around it.
- If no cut version exists, decide between a rear-sight mount and milling, and get the height and fitment answers from that specific maker first. The pages for the Glock 42, the Glock 29 and the Taurus G3 each say plainly that there is nothing to mount to.
- Once you know which footprint you are ending up with, pick the optic. Start with the footprint guide, then use the fitment finder to see what fits.