One thing I would add is to use the Loctite activator as well. It sets up very quickly and solved a lot of screws loosening. Just a thought.
Not a bad idea. Loctite is catalyzed by the ferrous materials and in the absence of oxygen. The tubes and bottles it comes in are actually permeable to oxygen (like the wraps on meat at the grocery store) to keep it from setting up in the tube. If you're screwing together less active materials, such as coated or stainless screws into anodized aluminum, the primer can be helpful.
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Not another dime.
If anyone is interested
The M&p core requires the factory trijicon RMR screws to mount it.
They are 6-32 and .496 long on my micrometer.
I’ve ordered some titanium torx head units from agency. Not because I wanted to pay $6 per screw but because the agency guys were kind enough to measure their screws for me despite not guaranteeing fitment with anything besides their optic cut.