The 14 cm/50 3rd Year Type naval gun was a Japanese low-angle weapon introduced during World War I. It served as the secondary armament in a number of Japanese dreadnoughts and as the main armament in light cruisers and some auxiliary ships. It was also the most common Japanese coast defense gun during World War II. Third year type refers to the Welin breech block on this gun. Breech block design began in 1914, the third year of the Taishō period. This breech block design was also used on Japanese 40 cm (16 inch), 20 cm (8 inch), 15.5 cm (6 inch), 12.7 cm (5 inch), and 12 cm (4.7 inch) naval guns.