A larger shell is not automatically the better armament if its slower rate of fire produces too few hits. In the pre-radar six-inch versus eight-inch cruiser comparison, the practical engagement ranges were close enough that the smaller weapon could exploit its much higher firing rate. Three or four times as many rounds create more chances to hit even when both guns achieve the same percentage accuracy. Several six-inch impacts can also damage more of the target and repeatedly test armor that survived the first strike. The example makes rate of fire and cumulative damage part of the calibre decision rather than treating shell weight alone as decisive.
Notable Point · 3:24-4:58
Rate of fire could outweigh shell weight
The six-inch versus eight-inch cruiser comparison shows how repeated hits can matter more than the greater damage of one heavier shell.