## Fm

Target Speed. Figure 4-14 reflects the differences in lateral speed for various angles of target movement for a target that is traveling at 8 mph at a distance of 150 meters from the firer. The angle of target movement is the angle between the target-firer line and the target's direction of movement. An 8-mph target moves 24 inches during the bullet's flight time. If the target is moving on a 15-degree angle, it moves 6 inches (the equivalent of 2 mph). For the firer to apply precise lead rules, he must accurately estimate speed, angle, and range to the target during the enemy soldier's brief exposure. The single-lead rule (place the trailing edge of the front sight post at target center) places effective fire on most high-priority combat targets. At 100 meters, the rule begins to break down for targets moving at slight and large angles.

Figure 4-14. Target movement (distance) at various angles.

Since the target lead is half the perceived width of the front sight post, at 100 meters the standard sight provides for 5.4 inches of lead for the M16A1 and M16A2 front sights (Figure 4-15, page 4-24).

Target Distance. The front sight post covers only a small part of close-in targets, providing for target hits on close targets moving at any angle and any speed. However, if the lead rule is applied on more distant targets moving at a slight angle—for example, 5 degrees at 100 meters — the bullet strikes forward of target center, about 4 inches with standard sights and about 7 inches with LLLSS sights. Therefore, soldiers are taught to fire at targets as though they are stationary until lateral movement is observed (15 degrees).

The rule provides for many speed-angle combinations that place the bullet within 2 inches of target center (Figure 4-16, page 4-25). Since the soldier is expected to fire a 12-inch group on moving targets at 100 meters, the rule provides for hits on the majority of targets. Even the worst case (a 90-degree target moving at 8 mph) would result in the shot-group center being located 9.8 inches behind target center. If bullets were evenly distributed within a 12-inch group, this would result in hitting the target 40 percent of the time.

Soldiers should be taught to increase their lead when targets are missed. This increases their probability of hitting all targets. The amount of additional lead required