Quote History Originally Posted By Ironmaker:
If windage is zero at 100 yards and a foot right at 300, barring actual wind, you have issues with the mount, the scope, canting, etc. Something is wrong.
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You bring up a good point.
My guess is this is partly a less than accurate 100yd zero, combined with range ammo that can be 2 to 3 MOA all by itself.
One good thing is that by dialing in his left/right windage at 300yrds, he will be getting a truer zero on the scope.
And try some different varieties of ammo. Different barrels sometimes shoot certain ammos poorly.
It's a little slow, but PMC .223 55gr is typically a quite accurate load for range/blasting ammo.
(Once you're pretty well dialed in, grab a box or two of some match ammo and really see what your rifle can do.)
OP, one thing you'll want to check is that your crosshairs are perfectly level with the action on your rifle.
At longer distances, all the little things add up to big things quickly.
Personally, I like the flashlight method for levelling the reticle.
How to: Square your Scope
I use this on top of the picatinny rail to make sure my AR is level, and then proceed with the flashlight method.
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