And in "that" time cannonbolls didn´t explode... you used them to bounce into a tightly-packed unit, to spread carnage and panic.
The exploding thingy is not really a explosion, it is when the boll bounde and then get wrong degree to bounce more and smach into the ground and shatters + trows dirt all over the place.
THe explosive cannonbolls were invented much later. This is what I know, I can be wrong.