I did put a sealing plate on mine, as there’s somewhat of a texture to the mounting plate. Since this is now my EDC gun I wanted to make sure it has a good seal.

The screws you’ll need to attach it to the plate are 6-32s. The length should be .390, not a common size. 3/8 may work. Better yet, get 1/2s and cut them back. Usually hex head are used and supplied with the sealing plate. When they’re that small, hex round off easy. I prefer Torx.


You can get the Torx from McMaster Carr.

https://www.mcmaster.com/catalog/125/3139

You can see the mounting plate on the 19. I had the 17 milled. I think that’s a better option.

Just a note, I had to file down the sides of my sealing plate due to it leaving a sharp edge exposed beyond the RMR.

I also noted the Gen 5 finish isn’t holding up too well. My mont old 19 looks worse than my Glocks from the early 90s!

It stinks getting older and having the front sight and rear sight blend together, doesn’t it? :fred:

 

I did put a sealing plate on mine, as there’s somewhat of a texture to the mounting plate. Since this is now my EDC gun I wanted to make sure it has a good seal.

The screws you’ll need to attach it to the plate are 6-32s. The length should be .390, not a common size. 3/8 may work. Better yet, get 1/2s and cut them back. Usually hex head are used and supplied with the sealing plate. When they’re that small, hex round off easy. I prefer Torx.


You can get the Torx from McMaster Carr.

https://www.mcmaster.com/catalog/125/3139

You can see the mounting plate on the 19. I had the 17 milled. I think that’s a better option.

Just a note, I had to file down the sides of my sealing plate due to it leaving a sharp edge exposed beyond the RMR.

I also noted the Gen 5 finish isn’t holding up too well. My mont old 19 looks worse than my Glocks from the early 90s!

It stinks getting older and having the front sight and rear sight blend together, doesn’t it? :fred:

Thanks very much for replying. Despite your detailed reply, I still have quite a few questions for you. Probably just my ignorance of the subject. Is the "sealing plate" actually necessary? If so, is it equally necessary for both Type 1 and Type 2? What does the sealing plate do? Does it waterproof or dustproof it? Why would it not be sealed enough with just the Glock plate only? Where do you get the best "sealing plate and why would any one be better than another? Thanks again.

 

I’m not sure if the sealing plate is absolutely necessary, I had one and I decided to use it.

The sealing plate just provides a flat smooth surface for the RMRs “gasket” to make a good seal. Actually, the sealing plate looks very similar to the steel banding that is used on some palletized cargo. If you had some flat, smooth, thin metal, you could easily make your own.

Here’s what Glocks adapter plates look like ( no this isn’t the one for the RMR, that’s currently on my 19) but you get the idea. With the Glock embossing it makes an uneven surface.

Why they couldn’t have marked and branded the plates on the side against the pistol, I’m not sure?

This is the bottom of the RMR, note the black gasket that seals the battery and electrical components.

I didn’t check to see if the gasket actually went over the embossed parts of the adapter plate. As I related, I had a sealing plate, so I thought I’d use it. Perhaps there’s someone on here that might have actually compared the gasket footprint with the adapter plate and embossment location?

Hope this helps.

 

Oh, also, to add, note on my milled G17, there is no need for a sealing plate, because it was machined smooth and provided good surface for sealing.

Maybe the RMRs gasket is thick enough to seal against Glock’s embossment? It wasn’t a gamble I was willing to take. When I put my pants on for the day, my Glock is on me too. I spend a good portion of my day outside working. My EDC stuff gets exposed to everything every day.

 

I have an RMR on a Gen 4 19 w/o the sealing plate and another RMR (Type 2) on a Gen 5 19. Both work fine.

 

Walt,

Is the gasket on the RMR thick enough to seal around the embossment? I’m asking, I didn’t check.

I live along a river and my son is stationed in the Keys. I spend a good portion of my life around the water. The reason I used the plate, is because I had it. If I didn’t, I probably would have put a thin bead of permatex around the RMR’s footprint on the sealing plate. Yeah, I know, maybe a little overkill, but accidental water immersion is a reality for me.

 

2 things watch that you don’t overt torque the rmr. Trijicon recommends just 11 or 12 inch pounds. Also keep a close eye on the lens that covers the laser. Both of my type 2’s had to have the lenses replaced within 50 rounds. If your dot turns into a large snowflake. The lens is gone

 

Is the "sealing plate" actually necessary? If so, is it equally necessary for both Type 1 and Type 2? What does the sealing plate do? Does it waterproof or dustproof it? Why would it not be sealed enough with just the Glock plate only?

I would definitely use the Trijicon sealing plate. See the following quote from the Trijicon website. "Note: If selecting an RMR for mounting
on the Glock® MOS system or the new
Springfield® OSP pistol, a Trijicon RMR®
Mounting kit (AC32064) is required."
That kit is easy to find and includes the proper length screws. Good luck!

 

I use the above trijicon plate on mine

 

Use the Trijicon brand sealing plate and screw kit.

There is a reason they make it.

The bottom of the rmr is open and requires a smooth surface for the Oring to seal.

The sealing plate is slightly wider than the MOS adapter so it makes everything fit the way it should.

 

Not only is the sealing plate required but the Trijicon kit has the CORRECT length screws which is even more critical. Do not try to use any screws that came with the pistol, MOS plates or the RMR as they are either too short or too long.

 

If you have a g19-17 etc you need a sealing plate to be water proof because the rmr is wider than the slide anyone who says my slide is milled flat doesn’t know that that’s not what makes a difference.


Sent from my iPhone using Glock Talk mobile app

 

If you have a g19-17 etc you need a sealing plate to be water proof because the rmr is wider than the slide anyone who says my slide is milled flat doesn’t know that that’s not what makes a difference.


Sent from my iPhone using Glock Talk mobile app

At least on my G17 that’s milled, the gaskets footprint rests well within the slide. No need for a sealing plate.

 

I actually called Trigicon help line last week! I asked about the dual illumination model and weather or not it needed a sealer plate. I was informed this model also requires a plate, just like the standard models. My thought was that since dual illumination does not have a battery I should not need a sealing plate!

There help line tech was very helpful.

You all should run the plate even in dry environments.

 

When should the RMR sealing plate be used?
The RMR sealing plate should be used if ANY of the following are true:

1. Mounting surface is interrupted, or
2. Mounting surface has through features, or
3. Mount surface does not fully encompass sealing boundary

 

I think I would have gotten the larger 6.5 moa dot