Moving Targets: Calculation
Equation
To manually calculate horizontal hold for moving targets, we will need to know:
- Target distance
- Target speed
- The time of flight for our bullet
(Target Speed / Distance) * Time of Flight * 1000 = Horizontal Lead in MRADs
Data Collection
Time of flight can be found in the ATragMX under the “RC” button in the top right of the screen or derived in an online ballistics program. As the ATragMX suite is not available in situations where manual ballistics are relevant, time of flight information should be recorded prior to operation start.
Human targets in Arma 3 only have a few predetermined movement speeds to utilize. Common speeds for human targets are listed below:
| Movement Name | Description | Speed |
|---|---|---|
| Full Sprint | Very fast run, weapon sways, head bobs significantly. | 5.0 m/s |
| Running | A moderate run, weapon sways, head remains stable. | 3.9 m/s |
| Combat Pace (gun up) | Fast walk, no appearance of running. Combat alert. | 3 m/s |
| Combat Pace (gun down) | A light jog, standard movement. | 2.8 m/s |
| Walking (gun down) | Relaxed walking, appearance of patrolling. | 1.4 m/s |
| Walking (gun up) | Very slow movement. Combat alert. | 1.35 m/s |
Calculation Example
Sgt McShooty is deployed as a Spotter (Manual) on a Honeybadger. He ranges a priority target at 800m, a shot that will have a time of flight of 1.5s. The target is moving in Combat Pace with his gun up.
(3 / 800m) * 1.5s * 1000 = 5.6 MRADs
Because target is moving from left to right, he tells his sniper to adjust 5.6 MRADs to the right, into the direction of travel.
Equation Limitations
This equation only provides a pinpoint accurate solution for targets that are moving perfectly perpendicular to the shooter. When a target moves at an angle, its horizontal velocity is in effect decreased, meaning the listed values will overestimate the target lead.
When targets do not move perpendicular to the shooter, decrease the output of this equation.
It should also be noted that although this equation provides great accuracy for leading moving targets, working through the math will only be practical when sniper teams have the opportunity to prepare hold values for moving targets ahead of time, to be utilized when targets present themselves. It should also be noted that when the target speed is unknown, this method cannot be utilized.
When values for moving targets cannot be calculated ahead of time, use a method of deliberate estimation.
