How Can I Sight in My AR15?

The AR15 designation refers generically to a civilian rifle derived from the military M16 design. These semiautomatic clones of the full-auto M16 are commercially available under a variety of brand names. Most standard versions are supplied with adjustable front and rear sights consisting of a twin-aperture sight in the rear (called a "peep sight") and a front blade sight. The larger rear aperture is for nighttime shooting at ranges from 0 to 200 meters and the smaller is for daylight shooting at 300 to 800 meters. Most standard shooting in daylight is done with the smaller aperture zeroed for accuracy from 0 to 800 meters.

  1. Setting up The Sights

    • Rotate the smaller aperture into the "up" position. Line up the windage indicator mark on the 0-200 aperture with the center line on the windage scale. Turn the elevation knob until the 8/3 mark on the range scale is aligned with the mark on the left side of the receiver. Turn the front sight post -- clockwise or counterclockwise, as required -- to bring the base of the front sight post flush with the top of the sight well.

    Taking Aim

    • Take the rifle to a target range or other location with a minimum of 100 yards of safe shooting distance. Aim carefully and fire a three-shot group at the bullseye of a paper target 25 meters away. Retrieve the target and evaluate the impact points of the shots.

    Making the Correction

    • Adjust elevation by turning the front sight post. To move the next group of shots up, rotate the front sight post clockwise; to move the next group of shots down, rotate the front sight post counterclockwise. Adjust windage by turning the windage knob at the rear sight. To move the next group of shots left, turn the windage knob counterclockwise; to move the next group of shots right, turn the windage knob clockwise.

    Final Adjustments

    • Aim and fire another three-shot group and evaluate the results. Continue to make adjustments and fire additional groups until you have a tight group of impacts on the bullseye. The small aperture is now zeroed for all ranges on the elevation knob; to strike a target at 500 meter range, for example, rotate the elevation knob to the "5" mark.