Check the scope for cant when mounting a scope. This makes a huge difference when sighting in. To make sure your vertical crosshair is indeed vertical to the action can be done by using a level on top of elevation knob, and a level on a flat suface of the reciever. I personally use two 36''rods, arrows, whatever is straight& won't flex at all and eyeball it level then torq the ring screws evenly. Double check after your done, it might take a few tries before your satisfied . Also eperiment with the way you torq the action srews.