Is that normal or a problem? I have a M4 upper + Aimpoint M2 + ARMS 40.

When I am aiming the target, I found the POI changed a bit if I raised up my viewpoint (over the rear sight). Usually, I tried to co-witness as much as I can. The red dot should be staying on the target no matter how you see from behind, right?

do you experience this problem? if you do, how you deal with it.

thanks.

best to use it (M2) with BOTH eyes open

there may be some difference at close range (<50m ~iirc)

check on line for the manaul for the M68 CCO

My unit uses the M2 also and we sometimes have the same issue.

The change in POI ( point of impact )is usually within 2.5 inches out to 50 meters. After 50 meters, I do not see the POI change. I know that they advertise that they are parallax free but I notice that if you use the same cheek weld for a grouping, the group is tight. If the shooter uses a different cheek weld, the POI changes sometimes. Tight group, but different POI. We noticed this on the EoTechs also.

The value of the optics for our use outweighed the " relatively" small variance at these distances.

The Aimpoint advertising says they are parallax free, but the US military manual FM3-22.9
( quoted below ) says not quite so within 50 meters.


                  CHAPTER 8
  ADVANCED OPTICS, LASERS, AND IRON SIGHTS
    (Phase V of Basic Rifle Marksmanship)

NOTE:
The M68 is a parallax free sight beyond 50-meters.