Mounting a Holosun 507k to a Glock 43x/48 MOS

I snagged a Glock 43x MOS a few months ago with the intention of mounting a Holosun 507K. The Glock MOS is setup for the RMSC, and while the 507k shares a similar footprint, the 507k does not have the recesses in the rear for the posts, and the front recesses are shorter than the Glock posts. (.029 vs .040 for this particular 507k/Glock combo)
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I am aware of the CHPWS adaptor plates that allow the 507k to be mounted to the Glock MOS, but if i modified the slide then I could use the factory height sights and it’s a direct mount vs the added variable of having a plate. So today I set up the Bridgeport mill and removed the rear posts completely, shortened the front posts to the correct height, and now it’s a perfect fit.
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Maynard

Amateur
Well done. Such a great overall CCW pistol.

I decided to try the G48 first but couldn't find a MOS model. After securing what I could, a local tool maker cut it for me.

 

Henny

Newbie
I realize this is an old thread, but it prompted me to join. By the way, first post!

I’ve been a consistent user of red dots on my handguns since 2014. I’m getting older, and my eyes aren’t what they used to be. I’ve always had RMRs on either a G17 or G19. My EDC is a Gen 5 G19 MOS w/ a RMR and a FCD plate

I did the same modifications to my 48MOS, remove the rear posts, lower the front ones, and put the Holosun on.

I am having one hell of a time finding M4x.7 screws that have the appropriate size head with either Torx or Hex drive. I checked the usual suspects, McMaster Carr, Fastenal, etc. I did find some Phillips heads that work, but phillips on a gun, it just doesn’t look right. The hex screws I have sit a little proud on the sight.

The second problem I have is during range sessions the sight shifting. Ive tried both blue Loctite and Vibratite VC3 on the screws. They eventually loosen during a single range session. I initially tried 15 in/lb. Within 3 magazines the sight would shift. I have no idea what I have them torqued to now. I guess the German standard of “gutentight”.

in my picture, you can see how the large diameter head screws are not flush.

My questions are, where do you source your screws, and how tight are you torquing them?4FD40B7B-5AB1-4E32-852F-09979129D7C8.jpeg
 
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