Hunting the Roll
Hunting the Roll was a gunnery technique by which a gunlayer or Director Layer would combine the use of continuous aim and firing on the roll to split the difference between those alternative methods of setting the elevation. In short, the trick was to adjust elevation occasionally to reduce the waiting time for the next opportunity to fire on the roll.
The primary virtue of this method was that it reduced the drawbacks of firing on the roll by reducing the amount of time the gun would have to wait before firing. It was a common trick for British director layers to employ, as they knew that the gunlayers would need a few moments to match up their elevation receivers. Consequently, the director layer might, if he saw guns ready to fire but the roll of his ship was likely to prevent firing for a considerable time, bump his elevation to a place where it would sooner meet the motion of his own ship. He would choose one that would reduce but not eliminate the wait, and then wait to fire on the roll.