My understanding is that Glock makes these currently in three different factory cuts. ACRO, RMR, and another I don’t recall. They are supposed to be agency purchase only, but some overruns find their way to dealers. My ACRO came with the optic, the RMR cut model (from AIM Surplus) did not. The RMR pocket is cut very oversize, enough so that the screws and recoil bosses are the sole support of the optic.
As an aside, the RMR pistols AIM had were by accident. They found out later they weren’t supposed to have gotten them. Also, since they had the covers installed they almost did not notice they were pre-cut.
My personal opinion is if I was going to use the RMR I would probably go MOS with a plate. I would prefer the added support of a close plate even with the extra screws needed to secure the plate. For an ACRO I think the pre-cut from the factory is the way to go.
Polite Professional
I saw some images of the gap on google search.
I wonder if sending the slide to a reputable machine shop for a tighter fitting optic, front recoil bosses and rear threaded recoil bosses is the better heavy-duty option when choosing RMR?
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