Instructions on scope installation
The procedure to sight in the rifles with A3 handles is basically the same as the A2 sight system listed in the owner’s manual. The A3 sight base has a shorter throw as the elevation stem of the base is not as long as the A2 sight base and can not be raised as high. Since the A3 sight has 1/2 MOA elevation instead of 1 MOA elevation you must click up twice on the elevation knob from the 6/3 mark to the "Z" for zero mark instead of one click used on the A2 elevation knob with the 8/3 mark.
To battle sight zero at 25 meters click up twice to the "Z" mark using the smaller aperture. Make elevation adjustments with the front sight post. Make the windage adjustment with the windage knob. The index marks are also twice the distance as the marks on the A2. Going past the 6/3 to the 4 mark again would be for 700 meters. It will not go high enough for 800 meters. The small aperture is still used for 300 and longer meter ranges while the larger aperture is used for the 0 to 200 meter range.