4-5 units of demi cannons pretty much flatten a star fort if you concentrate the fire. I think the size of the cannonball makes a big difference against buildings (pointing a finger at 64lb guns)Yes, but mortars can use exploding or carcass shot, which I think are more effective in the game than they were in real life. With 3 batteries of mortars and howitzers I've nearly wiped out the garrison of a fort. In the game round shot from cannon is pretty much useless against forts except for battering down the door.
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