Начальная скорость пули
The gun crews could fire a projectile once every six minutes. Muzzle velocity was 472 m/s and maximum elevation was 10° 30'. At maximum charge (204 kg?) and maximum elevation, a projectile could achieve a range of only 5,990 meters, but at that distance the projectile could still pierce 394 mm of steel (it is not clear if it was mild or hardened).