Training regulations. 435-275. Coast Artillery Corps: Service of the piece 16-inch guns, M1919 M2 and M1919 M3, on 16-inch barbette carriage, M1919, 16-inch gun, MK. 2 M1, on 16-inch barbette carriage, M1919 M1, and 16-inch howitzer, M1920, on 16-inch howitzer carriage, M1920, prepared under direction of chief of coast artillery; Mar. 20, 1933.