Cowitnessing with an AR

[Pivot]

This is my first post and I'm new to ARs so please bear with me.

I'm trying to set up a S&W M&P AR for optics. I am ordering the OR model without any sights at all (front or rear).

My plan is to run an Aimpoint M2 but would like to cowitness it with flip up BIUS. My question is how do I work it all out so everything is at the same height. I would like to have the Aimpoint on a Larue Mount. Do the BIUS come in different heights and if so how will I know if things are going to line up before placing my order?

Lastly, if anyone has recommendations on specific BIUS I am all ears.

[fyrelt]

i have a aimpoint m2 on my m4 with a larue 150 mount also my buis is a troy folding battlesight ,with the larue 150 mount this puts the buis in the bottom up your aimpoint,i like this better than the dot and the front sight post together,this is a 1/3 cowitness.hope this helps you.

[sammage]

Standard set of quality flip up BUIS will work, along wit an absolute co-witness mount. Some reading:
https://www.m4carbine.net/showthread.php?t=17049
https://www.m4carbine.net/showthread.php?t=35235
https://www.m4carbine.net/showthread.php?t=32903

[Belmont31R]

Why do you want a cowitness Aimpoint mount. You just prefer that height?

[Black Wrench]

My plan is to run an Aimpoint M2 but would like to cowitness it with flip up BIUS. My question is how do I work it all out so everything is at the same height. I would like to have the Aimpoint on a Larue Mount.


Larue does not make an absolute co witness mount for the aimpoint. I myself have an American Defense Aimpoint mount and love it as it is an absolute co witness. I wish they did but they don't, they are only lower 1/3 co-witness. Good luck and hope you like your setup..

[The_War_Wagon]

Why do you want a cowitness Aimpoint mount. You just prefer that height?

I know I do. COULD be my astigmatism, but i DON'T like second-guessing where the dot and the top of the sight post go, accounting for standoff, etc. - ESPECIALLY in a CQB situation where nanoseconds count!

The standard QRP mount may not be terribly sexy, but it WILL put your M2 right down on the rails in an absolute co-witness. Here's MINE on my BCM middy.

http://i212.photobucket.com/albums/cc305/The_War_Wagon/New%20build/BCM_rifle.jpg

With a LaRue fixed BUIS, it makes a perfect co-witness with the front sight post. You do have to get right down on it, regarding a good cheek weld with your stock, but I've had no problems with it. :cool:

[Sanpete]

The ORC model has a rail-level gas block so a matching set of troys would be perfect. You do not need a taller flip front.

Get the Larue mount but don't worry about 'absolute cowitness'. People get wound up on the cowitness term usually without really understanding what it even means. You will be able to use your flip sights throug your aimpoint tube just fine with the Larue mount.

And don't get the ORC. Get the model with the fixed front and Troy flip rear sights. The orc is not cheaper in the long run and flip front sights are a bad idea on a serious-stuff carbine. Just my thoughts.

[rattlesnake]

I know I do. COULD be my astigmatism, but i DON'T like second-guessing where the dot and the top of the sight post go, accounting for standoff, etc. - ESPECIALLY in a CQB situation where nanoseconds count!

The standard QRP mount may not be terribly sexy, but it WILL put your M2 right down on the rails in an absolute co-witness. Here's MINE on my BCM middy.

http://i212.photobucket.com/albums/cc305/The_War_Wagon/New%20build/BCM_rifle.jpg

With a LaRue fixed BUIS, it makes a perfect co-witness with the front sight post. You do have to get right down on it, regarding a good cheek weld with your stock, but I've had no problems with it. :cool:



Now that is a middy! Thanks for sharing.