$\text{If Attacker Precision value} \gt 10$
$\text{Precision score} = \text{Attacker Precision value} -7$
$\text{If Attacker Precision value} \le 10$
$\text{Precision score} = \frac{\text{Attacker Precision value}}{2} -2$
Precision roll: Precision score
$\pm$ Precision modifiers
+ DRN
Range: Number of squares from attacker to target square.
Diagonals count as 1.5 square
If Precision roll $\ge$ Range ⇒ The missile hits target square
If Precision roll is $\lt$ Range ⇒ The missile deviates from target square
The amount of deviation is equal to the range x 1.25 / Precision