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Discussion Starter · #1 ·
Hi
I am wondering if someone can answer my question about the height of the top rail in relation to the bore. Is it the same as an ar? It looks a lot higher to me due to the piston system.

The reason I ask is because when I get mine I will put my T1 on it but am not sure what mount will work best. On my ar I have the T1 on a Larue 660 qd that gives me a 1/3 cowitness and this works fine. My thoughts would be to get absolute cowitness with the acr due to the rail height from the bore. That way I can engage targets at farther distances easier.

Any thought?
 

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I'm glad you asked this as I'm curious myself. DSM stated he uses Troy Micros with the LaRue Mid-height and it works great for him. I guess the good thing about this platform is if an ACOG sits too high, you can always adjust the cheekweld up.
 

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Discussion Starter · #3 ·
Its not a matter of cheekweld. The acr will very comfortably support any optic in almost any mount. I am wondering if the mount needs to have the optic sit low so it's poa and poi aren't too far off when shooting cqb or or past 150m. For instance right now I just measured 1 1/8" from the center of the bore to the top of the top rail on my ar and wondering what the measurement for the acr is and for those that use optics at cqb and past 150m how bad is the shift from poa to poi.
 

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Just a quick wag w/ a tape measure but looked to be a little under 1 7/8" from center line of bore to top of the rail.

With a T1 in LaRue HK mount, 14.5" barrel, and a 50m zero it'll ring an 18" steel plate with a 12 o'clock hold at 300yds. At 200yds hold is center of course.

For me the HK height sights work. I've seen a few other ACR owners with them too. I think you'll be fine with any mount/sight combo you choose, though those tall LaRue T1 mounts will be very high in my humble opinion. I'd use their new absolute co-witness mount if I were using standard BUIS. Haven't tried mine with an ACOG yet, 'spose I could on the next trip.
 
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