This is a very cool quest to do and a very cool gun to unlock. To start this quest you must first travel to the USS Constitution, speak with the robot that approaches you. Then speak to "Ironsides" he will send you on a quest, do the quest and when you are asked to side with either ironsides or the scavengers. This is IMPORTANT, make sure you side with ironsides here. At the end of the quest you will get the "Broadsider" which is a cannon, literally its a cannon that shoots cannonballs !! Also as a side note if you revist the location and speak with ironside he will give you a unique hat

Cannon

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