"To declare War, grant Letters of Marque and Reprisal, and make Rules concerning Captures on Land and Water; "
That was more in line with “The Repo Man” ...
But, all kidding aside, The Second Amendment was crafted to address the free agency of the citizen to affect the means of his own defense, and that of his country. Those means were defined by the term “Arms” - a term confined to a very specific definition, as it was understood by those who wrote the Amendment.
“Arms” would include neither ordinance nor vessels; albeit it is understood that such a vessel may carry “arms” and be fitted with “ordinance,” as such grant by letters of Marque and Reprisal may permit.
Canon and the like were not an instrument of war typically kept in private hands, but rather such was allocated to an armory and maintained for “communal” defense.
I am wont to think that the local authorities would not be pleased to see Captain John Q. Private Citizen casually sailing up the Potomac with his well-fitted Frigate, sporting 24-pounder long guns, 32-pounder carronades; and 24-pounder bow chasers! Might make the common folk a wee bit nervous as to his intentions.