Can someone explain my Aimpoint Micro behaviour?

[Les K]

Hi All,

I was at my indoor range today and I noticed something odd with my aimpoint micro H1 that is mounted on a Ruger Mark 3. I sent the target out to the end of the 50 foot range and it shot fine and was hitting the spot that I stuck on the paper. My shooting partner brought the target in by half to 25 feet or so and it was shooting consistently low. We both tried it and even rested it on the bench and confirmed it. I mean it was about an inch to half an inch difference low.

When I adjusted the sight to hit ok at 25 feet, it then shot high at 50 feet when I ran the target back out. Again I rested the weapon on the bench and it really did fire high. This doesn't sound right to me. Is this normal for an aimpoint? Should it have to be adjusted each time for such a small difference in range? All hardware is tight and the sight is new and has not been bumped around at all. Any ideas would be greatly appreciated.

TIA,

Les.

[L4D]

It's normal a bullet that doesn't travel in a straight line. If your dead on @ 25 feet the bullet is still traveling up when it reaches 50 feet which will produce an impact higher than point of aim

[Mssr. Eleganté]

http://en.wikipedia.org/wiki/Trajectory

[AEW]

The problem is with the optic mount setup and the short distance. Since the centerline of the dot sight is mounted above the centerline of the bore by some amount, let's say 2", then the line-of-sight of the dot (aiming point) must be adjusted downward significantly (which in turn raises the centerline of the bore) in order to meet the path of the bullet at 25 feet. Because of this you will never be able to set the elevated red dot sight on one position to work at multiple distances in a 25 yard range. Ideally, the closer the centerline of the red dot sight is mounted to the centerline of the bore, the less deviation will occur at multiple distances. You can prove this just by shooting at the same 25 and 50 feets with open sights.

Regardless of what distance you set your red dot sight, imagine this......as the paper target comes ever closer to you and ultimately touches the muzzle of your gun, the dot is now pointed at a spot above the point of bullet impact on the target. This distance is equal to the distance between the centerlines of the sight & bore.

I have a red dot sight mounted on my Ruger Mk2 for decades and it initially boggled me too. For me I sight in my gun at 25 yards, and realize that the as I shoot at closer targets the bullet will impact lower than my point of aim.

[Les K]

The problem is with the optic mount setup and the short distance. Since the centerline of the dot sight is mounted above the centerline of the bore by some amount, let's say 2", then the line-of-sight of the dot (aiming point) must be adjusted downward significantly (which in turn raises the centerline of the bore) in order to meet the path of the bullet at 25 feet. Because of this you will never be able to set the elevated red dot sight on one position to work at multiple distances in a 25 yard range. Ideally, the closer the centerline of the red dot sight is mounted to the centerline of the bore, the less deviation will occur at multiple distances. You can prove this just by shooting at the same 25 and 50 feets with open sights.

Regardless of what distance you set your red dot sight, imagine this......as the paper target comes ever closer to you and ultimately touches the muzzle of your gun, the dot is now pointed at a spot above the point of bullet impact on the target. This distance is equal to the distance between the centerlines of the sight & bore.

I have a red dot sight mounted on my Ruger Mk2 for decades and it initially boggled me too. For me I sight in my gun at 25 yards, and realize that the as I shoot at closer targets the bullet will impact lower than my point of aim.

Ah Ha! This makes sense! That's why I didn't seem to have this issue with iron sights. It's mounted as low as it can go with the Aimpoint factory Weaver mount, but it is still significantly higher than the irons. Thanks!