Had a friend who pieced together a really nice AR with high end light weight components (Phase 5, cerekoted upper and lower receiver, bad button, etc)... and then proceeded to put a 40 dollar scope with no riser on top. He was convinced he had it set up like he wanted until he tried mine with the aimpoint on the co-witness riser. It was like an "ah ha" moment.
I thought all Aimpoints co-witnessed ?
I run Colt iron sights on my Colt. When people ask why I tell them it’s because I don’t have $600-$1400 to drop on an optic.