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Sorry to resurrect an old thread. I have a PS90 that someone wants me to fabricate a mount for that will replace the "peep sight" mount and allow him to use a Trijicon RMR, sitting a little lower to reduce the sight height.

He hasn't purchased the RMR yet because he's not sure it will work and doesn't want to spend $500 on it then be disappointed. Thus, I can't just fiddle with it, measure it, etc. to figure out what I must do. (making me apprehensive about taking on the project at all)

Once the factory peep-sight-picattiny rail is removed, the width between the two "wings" of the upper receiver section where the mount was, is anywhere from 1.015 to 1.030 inches.

My questions:

- What is the width of the RMR from outer side to outer side?

- Is the width consisted along the entire sight or does it change? (pics on web all make it look consistent)

I need to know this to determine of the mount I make will require the RMR to sit above the wings or if I can inset it between the wings to further reduce the sight height.

Any help anyone can could give would be greatly appreciated.
 

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Sorry to resurrect an old thread. I have a PS90 that someone wants me to fabricate a mount for that will replace the "peep sight" mount and allow him to use a Trijicon RMR, sitting a little lower to reduce the sight height.

He hasn't purchased the RMR yet because he's not sure it will work and doesn't want to spend $500 on it then be disappointed. Thus, I can't just fiddle with it, measure it, etc. to figure out what I must do. (making me apprehensive about taking on the project at all)

Once the factory peep-sight-picattiny rail is removed, the width between the two "wings" of the upper receiver section where the mount was, is anywhere from 1.015 to 1.030 inches.

My questions:

- What is the width of the RMR from outer side to outer side?

- Is the width consisted along the entire sight or does it change? (pics on web all make it look consistent)

I need to know this to determine of the mount I make will require the RMR to sit above the wings or if I can inset it between the wings to further reduce the sight height.

Any help anyone can could give would be greatly appreciated.
I think I'd just purchase the TROS mount....

 

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Welcome!!! :)
 

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Discussion Starter · #6 ·
Thanks for the welcomes and advice; that's very kind of you all.

The TROS mount doesn't look too bad.

Although, it looks like you could still reduce the sight height by a good half-inch if you were to have a mount specifically for the RMR that is about the same height as the picatinny rail of the TROS. Then you wouldn't have to use the picatinny adapter mount. I suppose it wouldn't be as versatile, though; you'd be stuck the RMR as your only sight option (not that that's a bad thing).

It's obvious, however, that you couldn't inset it between the wings, now that I look at it. You'd lose access to your windage adjustment.
 

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You could have the sight out front of the receiver.

This would give you the room to "lower" the sight further.
 

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Thanks for the welcomes and advice; that's very kind of you all.

The TROS mount doesn't look too bad.

Although, it looks like you could still reduce the sight height by a good half-inch if you were to have a mount specifically for the RMR that is about the same height as the picatinny rail of the TROS. Then you wouldn't have to use the picatinny adapter mount. I suppose it wouldn't be as versatile, though; you'd be stuck the RMR as your only sight option (not that that's a bad thing).

It's obvious, however, that you couldn't inset it between the wings, now that I look at it. You'd lose access to your windage adjustment.
I found the RMR on the rail mount too high for my liking. I'm going to make an RMR specific mount that attaches via screws to the side holes, but without the rail and need for a picatinny adapter. I think it would drop the RMR's view port by like 8 or 10mm.
I've entertained thoughts of removing the rear portion of the backup sights on the receiver so I could mount the RMR closer to my eye too, but I'm going to make the custom mount first. Need to take a few measurements of the RMR's mount so I can duplicate the pegs and arc on the front of the RMR.

-T
 

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Since it's been a few weeks, I'm wondering what the end result was - did you replace the backup sight? What arrangement have you ended up with?

I'm considering a Trijicon MRO with an appropriate mount. I'm also considering an RMR but have not decided how to dress up my dolly (PS90).

Update: I ended up purchasing the Trijicon...
 
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