The 330 mm guns had many faults. They were complex and moved with a weak system for such turrets (roughly the weight of an Italian 381 mm triple turret). They had two 100 hp engines (but only one was typically used). Despite the great range, elevation was only 35° (therefore the gun had a very high muzzle velocity of 870 m/s). The guns were coupled in two twin arrangement, sleeved in pairs. The turrets were heavily protected, and internally had a 25–40 mm bulkhead to separate the two twin mounts. This was important at Mers-El-Kébir, where a 381 mm shell hit in one of her turrets: the projectile penetrated the roof and killed everyone in the semi-turret, but the other pair of guns continued to operate.