M203 Quadrant Sight Assembly
The M203 quadrant sight assembly, which attaches to the left side of the rifle’s carrying handle, enables the grenadier to adjust for elevation and windage. This assembly consists of the sight, mounting screw, sight latch, rear sight aperture, sight aperture arm, front sight post, and sight post arm.
Clamp, Bracket Assembly, and Mounting Screw. The clamp and the bracket assembly hold the quadrant sight on the rifle’s carrying handle. The mounting screw inserts through the right side of the clamp and into the bracket assembly.
- Sight Arm and Range Quadrant. The sight arm mounts both the sight aperture arm (which holds the rear sight aperture) and the sight post arm (which holds the front sight post). This procedure allows the sight to pivot on the range quadrant to the desired range setting. The range quadrant is graduated in 25-meter increments from 50 to 400 meters. Applying rearward pressure on the sight latch releases the quadrant sight arm so it can move along the range quadrant. Centering the number in the rear sight aperture selects the desired range. Releasing the sight latch locks the sight in position.
- Front Sight Post. The front sight post mounts on the sight post arm by means of a pivot bracket. To prevent damage to the sights, keep the bracket closed when the sights are not in use. Use the sight post as follows to make minor adjustments in elevation when zeroing the launcher:
To decrease elevation, turn the elevation adjustment screw on the sight post clockwise; to increase elevation, turn it counterclockwise
To move the impact of the projectile 5 meters at a range of 200 meters, turn the elevation adjustment screw one full turn–360 degrees. To move the impact of the projectile 2.5 meters at a range of 200 meters, turn the elevation adjustment screw one half turn–180 degrees.
- Rear Sight Aperture. The rear sight aperture is on the sight aperture arm, which is attached to the rear portion of the quadrant sight arm. Use the rear sight aperture as follows to make minor adjustments in deflection (windage) when zeroing the launcher:
To move the impact to the left, press the rear sight aperture retainer down and move the rear sight aperture away from the barrel; to move to the right, move it toward the barrel.
To move the impact of the projectile 1.5 meters at a range of 200 meters, move the rear sight aperture one notch.