I just purchased the OR and am trying to figure out how to set it up. I have in my mind to put on iron flip-up sites and absolute co-witness with an EOTech XPS. I do not plan on leaving the flip up sites up while using the EoTech but want the option of using either one independently and no offset. My question is, can I fit an EoTech XPS (leaving room for a G33 or something similar) and still have room for all 3 eventually?

Congrats!

You absolutely should be able to fit all 3. Install your flip up BUIS as far back on the upper receiver as you can and you should have plenty of room to fit a magnifier and the Eotech no problem. Most magnifiers are built to mount a little farther forward and to flip up over the BUIS to save a little room.

This is not my rifle, but one of the first pics that popped up on Google. It has an A2 front post, but it gives you the general idea.



I'm not the hugest magnifier fan, but I was helping a younger vet on my range last week zero his rifle and new red dot with the exact set up. He loved the Eotech and thus decided on the dot and magnifier with his flip up BUIS. For me, it's just too crowded and too much weight when you can opt for a 1x4 scope and achieve pretty much the same thing. I will say though that I do like the Eotech reticle.

Sounds like you have not shot your OR yet. Good luck with her. Get the BUIS first and get to the range before deciding on the red dot set up, that's my opinion.

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Still carrying my S&W 642

I use Magpul BUIS and a EOTech XPs2 and have a perfect co-witness. The red dot sits precisely on top of the front post sight when the sights are up.

When you mount the EOTech, or any other optical sight, make a note of which rail number the sight is mounted on, that way you can remove and reinstall it without losing Zero. I switch between my scope and EOTech and never lose Zero on either one. I put the rail number on the bottom of each sight as a reminder.

Thanks for the info Kadonny and Lee in Quartzsite. Do you have the buis model you use? I want a non-polymer flip up that will line up correctly with the Eotech and give plenty of clearance for a possible magnifier later on.

My front sight is from Midwest Industries, made from aluminum.

MI-LFFR <br>Low Profile Flip Front Sight, locking

The rear is from Magpul:

https://www.magpul.com/products/mbus-sight-rear

I have never used a magnifier, but there should be enough room if you arrange the sights to accommodate one. The front sight is mounted on my gas block, that's why I used an aluminum one to handle the heat.

I don't use this set up, but there are lots of very good metal sights out there, just go looking. You can start with the Magpul Pros, they are metal. Stick with the metal because the OR front sight mounts to the front gas block, it can get hot. Good luck!

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Still carrying my S&W 642