Sweden's answer to the Sten gun that found favour with the CIA and the Ukrainians

Ever heard of the Swedish K? Well just after the Second World War ended Carl Gustaf developed Sweden's answer to the British Sten submachine gun – the Kpist m/45.

It's a simple and well-designed weapon that became known for being durable and reliable.

Initially used by the Swedish armed forces, it later became a favourite with the Americans.

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US forces nicknamed it the Swedish K because no one could say the Swedish word for submachine gun – kulsprutepistol.

It was also adopted for use by CIA operatives, as it could be fitted with a suppressor.

It is a blowback-operated, fully automatic firearm that fires from an open bolt.

It initially used two different removable magazines, the Finnish Suomi-type 50-round double-stack, single-feed 'coffin' magazine, later dropped from service, and then a more reliable 36-round double-stack, double-feed magazine.

With the help of a special speed-loading tool, a magazine can be filled in six seconds.

It has a shoulder stock made from thin steel tubing that folds forward and to the right, making it easy to carry in confined spaces and quick to deploy.

The sights consist of a front blade and flip-type rear sight, marked for 100 and 200 metres.

While long out of production, it was later manufactured under licence in Indonesia and Egypt under the name of Port Said.

There are reports of it still being used in conflicts around the world, including Ukraine.

Forces News has been talking to Jonathan Ferguson, Keeper of Firearms and Artillery at the Royal Armouries Museum in Leeds, to find out more.