305 mm/46 Model 1909 gun

• Name — 305 mm /46 Model 1909 • Origin — United Kingdom • Type — Naval gun Coastal artillery • Is Ranged — yes • Is Artillery — yes • Service — 1913–1937 • Used By — Italy • Wars — World War I • Designer — Elswick Vickers • Design Date — 1909 • Manufacturer — Armstrong Whitworth Vickers • Production Date — 1913 • Variants — Elswick Pattern "T" Vickers Mk "G" • Weight — Elswick Pattern "T": 69.3 t Vickers Mk "G" 63.5 t • Length — 14.5 m • Part Length — 14.02 m 46 caliber • Cartridge — Separate loading ammunition • Cartridge Weight — AP: 417.7 kg HE: 401.2 kg • Caliber — 302 mm • Rate — 2 rpm • Velocity — 840 m/s • Max Range — 24 km at +20° • Breech — Welin breech block • Elevation — -5° to +20° • Traverse — Dependent on ship and position

There were actually two guns from different manufacturers that were classified as the 305 mm /46 Model 1909. One gun was the Elswick Pattern "T" manufactured by Armstrong Whitworth, while the second was the Vickers Mk "G". Often, no distinction is made between the two guns and the model of gun fitted was not consistent by class of ship; in other words, the two models of gun were carried by different ships within the same class. There were subtle differences in the construction methods used for each gun and their weights were different. However, the guns dimensions were similar, their performance were considered to be equivalent, and both used the same ammunition and powder charges. However, the guns weren't interchangeable. In 1910 the life per barrel was given as 60 full or 200 reduced charges.

Elswick Pattern “T”: Had an inner A tube, A tube in two parts joined by screwed collar, B tube and half-length wire, jacket and short breech ring. A pneumatically operated Welin breech block was used and they were in hydraulic powered mounts. The Armstrong gun was similar to the Vickers gun, but weighed 69.3 metric tons (68.2 long tons). • Pattern “T” guns were fitted to the following ships: • Dante Alighieri • Giulio Cesare – Conte di Cavour-class • Duilio – Andrea Doria-class Vickers Mk "G": Was a fully wire-wound type with inner A, A, B tubes, jacket and breech ring. A pneumatically operated Welin breech block was used and they were in hydraulic powered mounts. The Vickers gun was similar to the Armstrong gun, but weighed 63.5 metric tons (62.5 metric tons). • Mk “G” guns were fitted to the following ships: • Andrea Doria – Andrea Doria-class • Leonardo da Vinci – Conte di Cavour-class • Conte di Cavour – Conte di Cavour-class