| Canon de 138 mm Modèle 1927 | |
| Origin: | France |
| Type: | Naval gun |
| Is Ranged: | YES |
| Is Explosive: | y |
| Is Artillery: | YES |
| Is Uk: | yes |
| Service: | 1927—1959 |
| Used By: | France |
| Wars: | World War II |
| Part Length: | about |
| Cartridge: | 130x900mm R Separate-loading, cased charge |
| Rate: | 8–10 rpm |
| Breech: | semi-automatic, horizontal sliding-block |
| Elevation: | -10° to +28° |
| Traverse: | approximately 300° |
The Canon de 138 mm Modèle 1927 was a medium-calibre gun of the French Navy used during World War II. It was derived from a German World War I design. It was used on the destroyers of the Aigle and Vauquelin classes and the Bougainville-class sloops.
The 40-calibre Mle 1927 was derived from the German World War I 15 cm L/45 UToF gun as mounted on the large torpedo boat SMS S113 received by France as war reparations. It copied the German gun's semi-automatic action and its horizontal sliding-block breech. It had an autofretted, monobloc barrel. It used 8.967kg (19.769lb) of powder to push a 40.6kg (89.5lb) shell to a muzzle velocity of 700m/s.[1]
The Mle 1927 was used in single centre-pivot mountings that weighed approximately 13t that were fitted with a 3mm thick gun shield. The mount could depress -10° and elevate to +28° which gave it a maximum range of 16600m (54,500feet).[1] The gun had a firing cycle of 4 or 5 seconds with its automatic spring rammer, but the dredger hoists transporting the shells and cartridge cases slowed the rate of fire down to 8-10 rounds per minute.[2]