No, Yes & Once
No, the main problem is that we, lay people in 2017, have a good idea how cannon work. And stone age people just don't. Not anything near.
Yes, a time traveller with some time to get prepared for just this occasion. You know, know-how, how to get the stuff he needs for this project. No cheating by going to the hardware store.
Once, so you have everything build you think you need, aka stone bombard. You aim, not sure at what, as there are no villages to speak of to our modern eyes. Maybe a hill fort? You light the fuse and a few seconds later you find yourself facing your maker, trying to explain what you were doing. You just fired the first stone bomb in history.
Stone just has the wrong properties to create a cannon. Let alone an exploding cannon ball. Even the myth-busters used wood with iron rings, firing multiple times.
With a short google search of
how to hollow out rocks does not show anything near what I think of as a Cannonball. There only seem to be hacked out basins.
Hollow Rock is a training exercise, so it will not help you much.
Mind that the thin walls of cannonballs are quite hard to make in stone. I am thinking 2 bowls together. But that will give problems with where they meet.
I think Andrew Dodds answer gets as close as you can to things exploding.