Why advertised gun rates mislead at sea

A quoted maximum often assumes a stationary mounting kept at the ideal loading angle, conditions unlike a maneuvering ship. Heavy guns usually had to return near horizontal before ammunition could be loaded safely, so every salvo could require elevation changes as well as training toward the target. Roll and pitch altered the effective loading angle and encouraged crews to choose a conservative setting rather than risk a shell moving incorrectly in the barrel. Ammunition supply also had to keep pace after the ready projectiles were gone. The meaningful measure was therefore the first fifty rounds under seagoing conditions, not the first few shots in a favorable test.