Does anyone have the answer for this. I am shooting with an Aimpoint CompM2. I have it dialed in at 50 yards but when I tried 100 yards, everything was really high and about 1 inch to the right. Also, I have heard that sighting in at 50 yards is best so that's why I did it. Can anyone help me with this?

Thanks

If you are on at 50, you should be around 1.75 - 2.00" high at 100.  Assumes line of sight 2.8" above bore, 3150 fps starting velocity, 55 grain ball (BC .243 according to Hornady).  

If you are off to the right, check your mounts.  Also concentrate very hard on trigger control, using your front pad.  Make absolutely sure you aren't jerking and pulling your shots.

Ballistics Calculator

Quoted: If you are on at 50, you should be around 1.75 - 2.00" high at 100.  Assumes line of sight 2.8" above bore, 3150 fps starting velocity, 55 grain ball (BC .243 according to Hornady).   If you are off to the right, check your mounts.  Also concentrate very hard on trigger control, using your front pad.  Make absolutely sure you aren't jerking and pulling your shots. Ballistics Calculator

Also, remember you are using a 4MOA dot (~4" at 100M). It is not a precision optic but a CQB optic, but as the saying goes "MOA of Man". I have engaged targets out to 300M+ with hits with an M2. If you need more precision, then look at a different optic system.

jtjpilot,

Listen to these guys and heed their advice.

Just to reiterate, if you do the IBZ @ 50yds, you WILL be hight @ 100yds.

I checked my 50yd zero yesterday and was bang-on @ the 50, but ~2" hight @ 100.

My setup consists of the following:
LMT 16" M4 profiled upper
Federal XM193 (haven't chronographed)
Aimpoint ML2
LaRue Aimpoint mount
LMT BUIS

All of my shots were easily in the 6" aiming black @ 100.  The Aimpoint is a FAST combat optic, or so I'm told.  I have also successfully engaged 300yd targets (18" steels) and have hit 28/28 (I load my 30rd mags to 28) while prone.

Good shootin,
Jim

How high above the bore to you have that gizmo mounted?

Some will disagree with this, but I'd zero it at 100 and settle for an inch or so low at fifty.

markm,

I'll have to get back to you on the Aimpoint height, perhaps someone else with a LaRue mount can jump in.

I do my initial zero @ 50yds, and if I'm ~2" hight @ the 100 then all is kosher in my book.  From there, I adjust my windage accordingly (if need be) to fine tune.

-Jim

Quoted: Does anyone have the answer for this. I am shooting with an Aimpoint CompM2.

How is it mounted?

If it's on a carry handle then rounds will be hitting about 4" high at 100y.

If its in a standard Aimpoint type mount on a flattop then it should be less than 2" high.

Another point - if the barrel is not free floated and you changed position and/or added sandbags/bipod/shooting sling/foward grip that can throw off your point of impact.

Quoted: markm, I'll have to get back to you on the Aimpoint height, perhaps someone else with a LaRue mount can jump in.

I guess a better question is...  Does the dot sit any higher than than the original Irons?  If so you'll be magnifiying the change of POI at a hundred due to the increase in Holdover.

The ballistics calculator link provided above allows you to define the height above the bore for your optic.  Higher boresights will result in hitting higher at 100 than a standard 2.8" boresight elevation.  I can't imagine they'd be a whole lot higher, but another 0.5 - 1.0" higher would be likely.  just plug the values in for your bullets BC, boresight height, starting velocity and zero range and you can see where you ought to be as range increases.