Check out my anti personell round useing a Scovill fuse. These were really nasty buggers. I found this in a abandoned house years ago. The M1907 Scovill "Combination timing and percussion fuse."was used extensively on shrapnel shells, which contained many balls.
The fuze was set so the balls would be ejected when the shell was on the downward part of its trajectory over enemy troops. The fuze is still attached to the top cone of the shrapnel shell which was ejected with the fuze to allow the balls to depart. The shell had a small gunpowder charge in the base to push the balls out.
Heres some more reading on the subject-