Have not handled an RMR on a rifle, but on a Glock 20, I had to get tall iron sights to assist in finding the red dot. Without a co-witness, it take me longer to find the dot, not something one would want on a DG rifle. May not be the same with a rifle.

Photo is with std sights before Trijicon supperssor sights were added. I wouldn't want a DG rifle without co-witness irons. And agree with 8x40 screws.

DF

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