Ballistics appear on the mission Bust up the safehouse from Vince Dubrowski (levels 20 - 24). There is just one of them in the mission and it will have some guards around. It can't move, nor has any attacks, nor any special abilities or effects. It has slightly less hit points than a Lieutenant of the same level. It is destructable, and any Villain or NPC caught in its blast will suffer some damage:
The contents of this crate must be destroyed!