MOS Platform Stability

Discussion in 'General Glocking' started by switch625, Sep 17, 2019.

  1. switch625

    switch625 S. S. Squirrel

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    I read somewhere the MOS cut will not hold the optic like it should and will come loose, you're better off getting a slide milled for your optic of choice. Any truth to this?
     
  2. thomgetch

    thomgetch

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    I have two MOS set up Glocks with 10s of thousands of contest rounds down the pipe both using red dots. Never once a problem solid as can be. I do use a little blue loctite when installing both the plate and the sight.
     

  3. sciolist

    sciolist On the Border

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    Obviously a slide properly milled for the specific optic is a lot more secure. Whether that's important to your application is another issue.
     
  4. mickiratt

    mickiratt

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    I think many of the problems with the Glock MOS system you read on the internet can be attributed to over torquing screws and/or using the wrong size screws.

    Sent from my SM-J700T using Tapatalk
     
  5. switch625

    switch625 S. S. Squirrel

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    It seems to be the MOS plate, only geting two threads in and only two posts is not enough to hold. Vibratite is recommended instead of loctite on other sites.
     
  6. Barry581

    Barry581

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    I've got a 41 MOS with a Vortex Venom and have never had an issue. A little blue loctite proper torque and go shoot.
     
  7. cciman

    cciman

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    Depends on the skill and focus of the installer. The closer the optic is to the slide itself makes a diff. If an adapter plate is needed in a universal setup like MOS, the optic is going to be up higher than a dedicated milled, and more parts involved- more parts, means more sources of coming loose.

    MOS is much cheaper/economical but less specific, and more flexible than a milled slide- and the surface is protected, whereas the milled slide may be raw, nor needs care.

    Measure the hole depths, make sure you get enough screw thread engagement.
     
  8. Cali.Glock

    Cali.Glock

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    If the correct screws are used on the MOS, there is not much to worry about.
     
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  9. Ranger357

    Ranger357 Just pixels

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    I think you combine the number of people using the wrong screws with the number of who post that loc-tite “does not work” (because they don’t understand the clean/degrease all surfaces, let cure thing) and a lot of the reputation is explained.

    But as above, sure a dedicated system is going to be stronger.
     
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  10. boilergonzo

    boilergonzo

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    My opinion is both true and false.

    False... it will come loose. I don't have any concerns about my MOS plate coming loose. It has been perfectly fine. Can it? Sure. Is it an exaggerated issue? I think so. Others in this thread are confirming they also are fine with the MOS (some adding Loctite, which those that mill also frequently do!).

    True... You are better off with a milled option. I think that is fair to say milling has some real advantages (lower height, better screw/thread contact), but the advantages are pretty small, and come at a significant cost. But do I think a direct-screwed optic is ultimately a wee bit stronger than one with a plate in between? Sure. I think it is safe to say milled is better in that regard. But I feel it is close to splitting hairs.

    If you need a lower sight, love to customize guns, and want it a bit over-engineered to sleep better at night, milling is a fine solution, and would serve you well.

    If you want a less expensive, more flexible option that won't become obsolete with new sights, won't damage the slide finish, and is a safe option and somewhat future-proof plan (Glock won't sell you replacement slides if you want to undo the cut or fix a mistake, or if a groovy new optic shows up on the market next year with a unique footprint... you will live with that milled slide forever, or buy third party parts to try to undo!), the MOS is a fine solution.

    Both are better at some things, and worse at others. My MOS has been solid. It is not something to worry about. But if you really want to optimize it, milling is a fine option, but it has upfront and possible future costs associated with it. What happens six years from now when that optic fails, and the new optic you want to replace it with does not share the exact same footprint? Perhaps a minor consideration for some, but a real point to think about.

    If you are fine with the height of the MOS, I'd just go with that. It is cheaper, easier, and flexible. It won't come flying off, as long as you use the correct plates and screws and care for it.
     
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  11. switch625

    switch625 S. S. Squirrel

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    Thanks for the info everyone
     
  12. GunsNweights87

    GunsNweights87

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    I have a g19 with a battle werks mill and rmr and a gen 5 mos 17 with rmr I use vibrating vc3 on both and never had an issue with either I also use the battle werks screws for the rmr to mos plate perfect size


    Sent from my iPhone using Glock Talk
     
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  13. GunsNweights87

    GunsNweights87

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    *vibratite vc3


    Sent from my iPhone using Glock Talk
     
  14. Nagoya10

    Nagoya10

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    Trijicon sells a kit to mount the RMR on the adapter plate for the MOS pistols. It consists of proper length screws and a thin plate to go under the RMR for sealing purposes. If the kit is not used you most definitely will have problems with the RMR coming loose or flying off. Otherwise there is no problem even after thousands of rounds. The oft used excuse/marketing ploy is to state the special cut slide is the only one worthy of consideration but it is entirely untrue. The Glock MOS system works great, as long as you use the right parts.
     
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  15. Valor1

    Valor1 Range Bum

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    My glock 17 mos is on its 5k count. No problem with the vortex venom mounted on it.
     
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  16. Dannyi

    Dannyi

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    G19.4 MOS with Shield, no problems.
    A little careful time and a dab of loctite, done deal.
    [​IMG]
     
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  17. Jarrod37387

    Jarrod37387

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    I have a couple MOS models. My G45 MOS has a Shield RMS on it with the Shield adapter. It sits low enough to co-witness with stock height sights and fills the gap between the optic and the edges of the cut so the optic is on there pretty secure. It also has posts that the screws go into so you get 7 or 8 threads of engagement holding the optic down.
    20190904_181048.jpg 20190904_180405.jpg

    On my Gen 4 19 MOS I have an RMR along with Ameriglo GL-429 suppressor height sights. I used the Glock MOS plate for a couple of years and a lot of rounds. I decided I wanted to try the C&HPWS plate so i ordered one. It does pretty much the same thing for the RMR (or several other mini reflex sights) that the Shield plate does. C&HPWS also ships the plate with all of the screws and hex keys you'll need and you do not need a separate sealing plate since it is the correct width. Here is a link so you can take a look:
    http://www.chpws.com/product/holosun-glock-mos-adapter-plate-v3

    I have no issues with the MOS platform and find it handy if i decide i want to try a different optic. I get that a milled slide has the optic sitting lower, but, it's only a few millimeters and it doesn't affect sight picture or being able to zero the optic in the slightest.
     
  18. jsjac

    jsjac

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    I have a couple of MOS slides and three cut slides.
    I have a 34,27 and a 19 with cuts. The 27 is going to be my new carry gun once I get it sufficiently tested.
    I have a 34 and a 35 that have MOS slides.
    I find no difference in durability so far.
    I have been using the DPP sights on all except the 27. It has a shield RMSC on it.
     
  19. BASE 772

    BASE 772

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    Thousands of rounds through my MOS with zero problems.