Suffren alone carried the 75 mm Model 1924, a higher-elevation development of a prewar weapon whose practical rate of fire fell well below the theoretical figure as crews handled 12 kg fixed rounds. It was credible when selected in the 1920s even though air warfare had overtaken it by 1939-41. Her sisters received 90 mm guns with semi-automatic breeches. Those weapons could manage about 12 to 15 rounds per minute at lower elevation but closer to ten above 60 degrees, where loading became difficult. With 500 rounds per gun, the ship carried roughly fifty minutes of heavy anti-aircraft fire at a practical ten-round rate, a useful measure of magazine endurance as well as gun performance.
Chapter · 23:35-28:54
From Suffren's 75 mm guns to the class's 90 mm battery
The original 75 mm weapon was credible for the 1920s, while the later ships' heavier 90 mm guns offered useful dual-purpose performance with elevation-dependent handling limits.