This Carl Gustaf M/45 also known as the Swedish K submachine gun was found in 2008 in Sweden by a group during a chainsaw training exercise.

Caliber: 9x19mm Luger/Parabellum/NATO

Weight: 3.43 kg empty

Length (stock closed/open): 552 / 806 mm

Barrel length: 203 mm

Rate of fire: 600 rounds per minute

Magazine capacity: 36 or 50 rounds

Effective range: 200 meters

The M/45 is a simple blowback gun the fires from an open bolt. It was created in 1945 and used by the Swedish military.

Here’s one not stuck in a tree:

And here’s some in use by Swedish competition shooters. They’ve been modified with brass catchers and sight hoods.

Video [14:55] https://youtu.be/lYGthBDzt8o?si=

https://www.thefirearmblog.com/blog/2018/03/02/carl-gustaf-kpist-m45-submachine-gun-found-15-yards-tree/