120 mm Italian naval gun

Italian 120 millimetre naval guns were standard main armament on Italian destroyers and were widely used on various other ships and coastal artillery. The 50-calibre guns used a charge of 9.7 kilograms (21 lb) of smokeless powder to push a 23.49-kilogram (51.8 lb) projectile to a velocity of 950 metres (3,120 ft) per second. Velocity was later reduced to 920 metres (3,020 ft) per second, which gave a maximum range of 19.6 kilometres (12.2 mi) at 45°  elevation or 18.2 kilometres (11.3 mi) at 35°  elevation. Variants of similar designs were built by Ansaldo, OTO, Vickers, Schneider, Canet and Armstrong. Older and shorter-barreled guns have different ballistics as noted below.

These were British QF Mark I and III guns used as coastal artillery and as star shell guns aboard Littorio-class battleships.

These guns formed the original secondary battery of Andrea Doria and Conte di Cavour-class battleships and were later used for coastal artillery. They fired a 22.75-kilogram (50.2 lb) projectile at 840 metres (2,760 ft) per second.

These guns were developed from the older 40-calibre models and installed as coastal artillery and aboard troopships and armed merchant cruisers. They fired a 51-pound (23 kg) projectile at 750 metres (2,460 ft) per second. Range was 12.6 kilometres (7.8 mi) at the maximum elevation of 30° .

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