same principles i believe...
in the mission or a cutscene, you call an artillery script right? same story in intros. if you're talking about single tanks, then to make them fire on a given target, create a marker or a game logic (or even a real enemy target), then use
name_of_tank dotarget name_of_target
name_of_tank dofire name_of_target
this will make the tank fire at the target until the target is kaput. for a barrage you really need a script, as from experience i've had difficulties doing it the old-fashioned way
hope this enlightens
b