Ironclad (1973)

From the introduction: "Ironclad is intended to be a set of quick-moving, hard hitting rules, best suited for those who wish to sacrifice a certain amount of realism for the sake of the game. It is not intended to be comprehensive and cover every possible situation that could arise out of the U.S. civil war. It is, rather, a playable game... a framework around which you can build as elaborate set of rules as you wish."..."The game is extremely bloody."
The game is intended for 1:1200 miniatures on a table top of at least 3' by 5'. Each turn represents 5 minutes of real time, and ships move 1" (100 yards) for every knot of speed. Each ship gets a card with hit boxes for armor, speed, midships, stacks, draft, guns, and battering ram. A ship is sunk when all draft boxes are gone. Forts get similar cards.
The rules are only about 12 pages, plus a couple more for charts, pictures and background data. There are charts for penetrating and non-penetrating gunfire, critical hits, lucky hits, ramming, minefields, and loss of stack. There are also three different turning circles.