I'm having my m&p full size 9mm milled by a local smith.
Do I need a plate or mounting option for a non-core pistol?
How do the rmr' mount to the slide?

Burris makes a mount that would fit were the rear sight is and screw the reflex optic to that BUT I would sell the pistol and buy a CORE.

Click SPECS - FastFire? Mounts | Burris Optics

Trijicon sells the mounting plates...

https://www.trijicon.com/na_en/produ...sories&mid=RMR

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M&P 9mm 5" Pro
M&P 9mm Shield

You can also get them from Amazon for less money although I didn't hang around long enough to see who they are made by

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M&P 9mm 5" Pro
M&P 9mm Shield

I'd reach out to David Bowie at Smith and Wesson M & P. He did mine and his work is impeccable.
Keith

If you have the gunsmith mill the slide specifically for the RMR then an RMR, and only an RMR, will mount directly to the slide no plate needed.

If you're not sure about this already, you should definitely make sure you and the gunsmith are on the same page before he cuts into your slide.

Speed Shooter Specialties sells this little gem for $54: Trijicon RMR Sight Mount, S&W M&P [1998] - $54.00 : Welcome to Speed Shooter Specialties

It's one way to test the sight before taking the one way trip of milling.

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Freedom isn't free.

Milling a slide and threading the mounting holes for a specific sight, along with changing your iron sights to get the correct placement and height for cowitnessing, is not just machining. There is math and experience involved. I would not trust a local 'smith to do it correctly unless he has done so on a dozen others guys' guns--successfully.

A couple of years ago I had a buddy show me his brand new RDS on top of a .45 ACP. The sight was obviously skewed laterally. When I pointed it out, my buddy said he had thought the same thing but didn't know what to do about his $2,000 gun being ruined.

You only do this once and a lot goes into doing it correctly. Fore/aft positioning, cut depth, perfect dimensions, screw hole placement, size and depth, refinish, iron sight removal and new sight installations.

Agree totally. A friend of mine had an RMR installed on a 1911 by one of the foremost gunsmiths in the US. Won't tell you his name but he's very famous; but, he'd never mounted an RMR on any gun. Bottom line, my buddy could not sight the gun in because the adjustment screws ran out of adjustment. We had to shim the back of the sight up by about .010" and then everything was A OK. But I just had to shake my head at that one. I had an RMR installed on my 1911 for Bullseye several years ago. David Sams had built the gun and was familiar with the sight and its installation. Bottom line: it works perfectly in all respects.





The mount it sits on comes from Trijicon as a simple block of steel and is made to be shaped by the gunsmith.

Keith