Gen5 G17 and M&P 2.0 Comparison shoot

[zcap]

The CORE system design uses a single set of fasteners across two sets of bosses on two planes. This design means cumulative tolerance stacking occurs across the slide to plate interface and the plate to optic interface. In my experience, this is the major practical problem with the CORE design. Unless each of the optic, the optic plate and slide cut mate up tightly as a unit, the effectiveness of recoil bosses is compromised and proportionally more force is transferred via the optic screws. Regardless of how tight S&W executes their slide cuts, in practice optic plates have looser tolerances and optic tolerances are all over the map depending on the manufacturer and model.

The MOS and most other mounting systems use a separate set of fasteners and recoil bosses on each interface between planes. This design limits cumulative tolerance stacking across interfaces and in practice means plate manufactures can make their optic to plate and plate to slide interfaces tighter because they don't have to worry about a slight misfit on one interface compromising the fit on the other interface.

This may also contribute to the divergent experiences with the CORE system. A particular model of optic on a particular manufacture's plates against a particular run of M&P CORE pistols may work extremely well. Changing any one of these variables could result in a different experience.

[SoCalDep]

The CORE system design uses a single set of fasteners across two sets of bosses on two planes. This design means cumulative tolerance stacking occurs across the slide to plate interface and the plate to optic interface. In my experience, this is the major practical problem with the CORE design. Unless each of the optic, the optic plate and slide cut mate up tightly as a unit, the effectiveness of recoil bosses is compromised and proportionally more force is transferred via the optic screws. Regardless of how tight S&W executes their slide cuts, in practice optic plates have looser tolerances and optic tolerances are all over the map depending on the manufacturer and model.

The MOS and most other mounting systems use a separate set of fasteners and recoil bosses on each interface between planes. This design limits cumulative tolerance stacking across interfaces and in practice means plate manufactures can make their optic to plate and plate to slide interfaces tighter because they don't have to worry about a slight misfit on one interface compromising the fit on the other interface.

This may also contribute to the divergent experiences with the CORE system. A particular model of optic on a particular manufacture's plates against a particular run of M&P CORE pistols may work extremely well. Changing any one of these variables could result in a different experience.

I do agree with you regarding plate fit. That’s why I believe the factory metal plate is best. I’ve never seen one that isn’t a very tight fit. I’m sure some exist. As for some other plates, they don’t necessarily have the same fit and that can be problematic. I’m not sure if it’s more a factor of tolerance variation or that S&W originally designed their plates to work with the round bosses and the slight protrusions that seem to be present, particularly on the front boss. I’ve seen aftermarket plates that simply didn’t line up with the bosses and screw holes. In one case our answer was to mount the plate, hand-tighten the screws, then beat the crap out of the plate until it was flush, which allowed the protrusions on the front boss to deform the softer aluminum plate - then go through the mounting procedure.

[GJM]

I have had mixed experiences with the CORE system.

Most of my rounds were on my CO pistols, and I didn't have any problems with four pistols. However, I used a Romeo 3 Max, and a C-More plate. The C More plate bolted to the CORE holes like a MOS plate, and the R 3 Max bolted to the plate, so this wasn't really a test of the CORE system and filler plates.

On the negative side, I had a screw shear using a CORE plate, and S&W replaced the slide. I also had the bosses deform on a plastic CORE plate. The OEM metal CORE plates weren't available to me. I also had a bad experience with CHPWS getting a 509T plate to hold, and had to return the pistol three times to them, as the plate kept coming loose. From memory, I believe I recall reports of optics flying off the 10mm pistols, but I can't swear to it.

I have one slide direct milled for a RMR footprint and I like that more.

[SoCalDep]

I agree about direct milling = better if you are good with a single footprint. We had problems with the C&H 509T plates as well. I sent them a multi-page document with lots of photos of what we thought the cause was. C&H did a good job of addressing the issues with a redesigned plate, but the redesign was the one that didn’t quite fit and required a good beating to seat it prior to mounting.

I think we probably discussed that at some point around the beginning of 2022 but the thread is likely old and buried.

We deformed the bosses on a plastic plate as well, but only after the optic came loose. It seems, based on examining some high round count plastic plates, that as long as everything stays tight they are fine. If the screws loosen the movement of the optic will pretty quickly start deforming the bosses. We also learned that firing 1,985 rounds in about 20 minutes is quite abusive and probably not indicative of real-world conditions.

I’m still not a huge fan of plastic in principle as an optic mounting material.

[GJM]

I find the most objectionable aspect of the core pistols is the ridiculously tall and sharp back up sights they put on them. These sights seem the antithesis of what you would want for appendix carry against your skin and under clothing!

[Lunker]

All this optic plate talk has piqued my interest.
Most of the aftermarket options are aluminum. Some seem like they might offer added functionality, or at least durability over plastic.

Calculated Kinetics - Aluminum. Elevates the optic pretty high for their “dogtag” that supposedly reduces LCI debris from gunking up the optic glass.
https://www.calculatedkinetics.us/pr...ag-optic-plate

C&H - Aluminum. Pretty close in function to factory plates.
https://chpws.com/product/sw-core-2-0-1-975/

Forward Controls - Aluminum. A really thick plate that end up offsetting the optic from the slide screws, so you end up with one set screwing the plate to the slide, and another screwing the optic to the plate (MOS like). The optic sits really high and barely cowitnesses with the already really tall factory sights
https://www.forwardcontrolsdesign.co...RMR_p_498.html

CNC Pros - Steel plate.
https://thecncpros.com/products/ols/products/mp-to

I don’t have any knowledge, good or bad, about these. They are just what came back after a quick Google.

[SoCalDep]

I would go steel or titanium over aluminum which I’d go with over plastic assuming the plate fits and isn’t too tall. The problem is that a lot of plates either don’t fit or are too tall. I’ve had good luck with Eleven71 titanium plates and again, my gold-standard is the factory steel plate.

[Wonder9]

I've been using the Calculated Kinetics plate since it stops LCI blowback. Only have about 250 rounds with it on, but it's been good so far even with a lower 1/5 co-witness. Just recently got my JMCK IWB3 for it, so I'm going to be working more with the M&P.

I'll probably try the FCD plate on my M&P Spec Series because their Glock plates are the heat.

[ldunnmobile]

I've been using the Calculated Kinetics plate since it stops LCI blowback. Only have about 250 rounds with it on, but it's been good so far even with a lower 1/5 co-witness. Just recently got my JMCK IWB3 for it, so I'm going to be working more with the M&P.

I'll probably try the FCD plate on my M&P Spec Series because their Glock plates are the heat.

I’ve been curious about the dog tag Calculated Kinetics one.

[45dotACP]

All this as I'm pondering the idea of getting a M&P 2.0 CORE model....

Maybe I'd just get the Holosun SCS set up for the S&W