In what year was the US naval gun designed for the battleships to help Argentina counter Brazil's two "Minas Geraes"- class battleships?
Rivadavia-class battleship:  Named "Rivadavia" and "Moreno" after important figures in Argentine history, they were Argentina's entry in the South American dreadnought race and a counter to Brazil's two "Minas Geraes"-class battleship s.
i don't know