# Bofors 57 mm Naval Automatic Gun L/60

Bofors 57 mm Naval Automatic Gun L/60 (Swedish: 57 mm sjöautomatkanon L/60 (57 mm SAK 60)), also known as 57 mm/60 (2.25") SAK Model 1950 and the like (full English product name: Bofors 57 mm Automatic A.A. Gun L/60 In Stabilized Twin Turret), was a twin-barreled 57 mm (2.2 in) caliber fully automatic dual purpose naval artillery piece designed by the Swedish arms manufacturer Bofors from the early 1940s to the early 1950s to meet a request from the Dutch Navy. Besides the Dutch Navy, the weapon was also adopted by the Swedish and the French Navy, most predominantly by the latter.

## Design

The Bofors 57 mm Naval Automatic Gun L/60 is at its core a scaled up version of the famous Bofors 40 mm Automatic Gun L/70, but constructed as a twin-gun system sharing the same receiver/mantle with ammunition feeding from the sides into each gun. The guns were water-cooled and fed by large 80-cartridge magazines that allowed several long bursts to be fired without reloading.
* French "57mm/60 modèle 1951" on display at Port-Louis naval museum.
* French "57mm/60 modèle 1951" on display at Port-Louis naval museum.

## Use in the Dutch Navy

The Dutch were the initial users of the Bofors 57 mm Naval Automatic Gun L/60. As part of rebuilding the Dutch Navy post World War II, the Dutch Navy had requested several naval gun systems to be developed by Bofors for their next generation of naval-vessels, one being a twin-barreled 57 mm dual-purpose gun for the planned De Zeven Provinciën-class cruisers HNLMS De Ruyter and De Zeven Provinciën. This request led to the creation of the Bofors 57 mm Naval Automatic Gun L/60, which entered active service with the Dutch Navy in 1953 mounted on the cruisers De Ruyter and De Zeven Provinciën.

## Use in the Swedish Navy

Following the Dutch example, the Swedish navy decided to acquire the new 57 mm system for a new generation of destroyers in 1950. In Swedish service the weapon was fitted to the Halland-class destroyers HSwMS Halland and Småland, both of which entered service in 1956. The weapon was initially designated 57 mm automatkanon m/50 (57 mm akan m/50), meaning "57 mm autocannon m/50", but around 1970 the weapon was redesignated to 57 mm torndubbelautomatpjäs m/50 (57 mm tdblapjäs m/50), meaning "57 mm turret double automatic piece m/50" (literal).
The gun was in use until the Halland-class destroyers were taken out of service.

## Use in the French Navy

The Bofors 57 mm L/60 naval gun was also purchased by the French Navy and came to serve on a number of naval-vessels under the designation 57mm/60 modèle 1951 (57mm/60 mle 51) from 1952 onward, although primarily post 1956. The French navy version of the system featured a French designed naval mount that maintained the system in mechanical equilibrium, even when firing. The French mounting was some 8 tons lighter than the Dutch/Swedish version.
In French service the gun notably armed light escorts as main guns and larger ships as secondary guns. The following French ships were armed with the 57mm/60 mle 51 system:
* The battleship Jean Bart (1952 retrofit)
* The anti-aircraft cruiser De Grasse
* The anti-aircraft cruiser Colbert
* Le Normand-class frigates
* T 47-class fleet escorts (also known as the Surcouf class)
* T 53-class fleet escorts