The reduction in weight achieved by the removal of one of these turrets allowed for the adoption of new dual-purpose 100 mm Mle 1937 autocannon; six of these twin mounts were to be installed around the forward superstructure, four abreast the rear superstructure and two between the conning tower and the main battery. These were the same guns that had been adopted for "Richelieu" during construction, but the mounts were new, fully enclosed gun turrets compared to the open mounts aboard the earlier vessel. Six new 37 mm ACAD twin mounts would be added to supplement the 100 mm guns; four of these would be placed a deck higher and further inboard than the 100 mm guns aft and the other two would be placed on either side of the superfiring main turret. These guns proved to be problematic during development, owing to excessive barrel wear that resulted from its very high muzzle velocity and the weight of the projectile. Efforts to correct the problem had delayed the adoption of this gun for the earlier "Richelieu"s and it never actually entered service apart from a prototype installed on the aviso . Additional fire control directors were installed for the new guns.