Leonardo da Vinci’s rapid-firing organ gun design included 33 barrels.
The weapon arranged its small cannons in three rows of eleven on a wheeled frame. Because one row could be fired while another cooled or was reloaded, the design aimed to maintain a more continuous rate of fire than a single cannon. The arrangement resembles the pipes of a musical organ, which explains the weapon’s name.
Leonardo developed the concept in the late fifteenth century, when artillery was becoming increasingly important in European warfare. His design addressed a major problem of early gunpowder weapons: firing, cooling, and reloading were slow and hazardous.
The organ gun was not a modern machine gun. It still relied on individual gun barrels and gunpowder charges, and there is no firm evidence that Leonardo’s exact design entered combat. “33” refers to the number of barrels in the famous design, not the number of shots it could fire simultaneously.