Co-Witness on EOTech

[mala in se]

Can someone school me on co-witnessing an EOTech. I have a 512 on top of a flat top AR. No QD mount, no riser, just the optic on the flat upper rail.

Is that considered a full co-witness? I've seen some people referring to BUIS and advisng 1/2, 2/3 co-witness.

[trapshot68]

This image explains it best.

With front post and rear sight, the reticle should be centered in between the two.

What 1/2 and 1/3 means is where the sight plane is in relation to the optical sight.

On the left is 1/2 witness (halfway through the Eotech). On the right is 1/3 or bottom 1/3 since it's, yep, on the bottom third of the Optical sight.

[joelogic]

What you have is the 1/2 co-witness. The other kind is a 1/3 co-witness.

1/2 is fine depending upon your needs. I like 1/3 because if offers a larger unobstructed field of view but I dont like my eotech any higher off the bore than it needs to be. So I mount my eotech to the rail and fold my sights.

[trapshot68]

that was always one thing I liked about the eotech. Mount included. I had to get one for my Aimpoint, but I use flip sights anyways, so I didn't have to get a higher mount.