Marine complements are compared with both a ship's total crew and its number of guns. One historical rule of thumb places the detachment at about an eighth to a tenth of the complement. Marines could serve at guns as well as perform their other duties, but later specialisation complicates treating every marine as an interchangeable naval gunner. The steam-era comparison includes marines assigned to a gun useful for supporting troops ashore. These examples inform the Leander staffing question without establishing one complement formula for all periods.
Notable Point · 3:34:38-3:37:34
Marines as gun crews and the limits of dual duties
Historical marine gunnery duties provide a comparison for deciding whether a fictional detachment can also operate the ship's weapons.