The 18-pounder short gun was an intermediary calibre piece of artillery mounted on warships and merchantmen of the Age of sail. It was a lighter version of the 18-pounder long gun, compromising power and range for weight.

18-pounder short gun
1/4th Scale model of an 18-pounder short gun, model 1824. On display at the Musée national de la Marine, Paris.
Type	Naval gun
Place of origin	France
Service history
Used by	France, Spain, Great Britain, Netherlands, Sweden, United States
Specifications
Shell weight	8.8 kg
Calibre	138.7 mm[1]

In his discussion of the single-ship action in which the French frigate Piémontaise captured the East Indiaman Warren Hastings on 11 June 1805, the naval historian William James compared the 18-pounder medium guns on Warren Hastings with the 18-pounder long guns that the British Royal Navy used. The medium 18-pounder was 6 ft (1.8 m) long, and weighed 26+3⁄4 long cwt (3,000 lb; 1,360 kg); the Royal Navy's long 18-pounder was 9 ft (2.7 m) and weighed 42+1⁄2 long cwt (4,760 lb; 2,160 kg).^[2]