You take shots in the area of your target, ranging above and below, until you have allowed for errors and can home in on the bullseye.

• 这里适用的意思应为:夹叉射击,指的是大炮不直接射击目标,而是先射击目标周围测定范围,再最终一举击中目标。根据下面的解释,也是这种意思。