Here's a study of the defensive artillery placed on the regular pentagonal fort. Only 1 and a half bastions are studied (and armed with cannons) in this case.

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The cannon type I'm supposing is being used are french naval cannons of 36 lbs. Its point blank range is of 650 meters (the arches shown on the image), but its maximum range is of 3300 meters (outermost circle). These cannons need a recharge time of 8 minutes after being shot.