This is a tactic me and my friend figured out yesterday during the double reputation day. The way this game works the more hits you do the more rep you get, well i figured out a way to exploit this for cannons,
Hitting the sails counts towards hits on the ships! Just get a friend to take a ship out and let you cannon a large ships sails with regular cannonballs for a few seconds then sink it with broadsides and boom, easy cannon rep
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