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=
Tell me more about this “chainsaw training exercise”
I can’t find much on it but it seems to me Sweden has land designated for army training. Presumably they have combat engineers or a similar occupation who need to be trained with chainsaws, and they took those men out into a space on that land where someone has previously forgotten this SMG. I’d assume that they were tasked with cutting down random trees until they could safely and comfortablely use chainsaws.
TLDR: Guys being dudes as mandated by the Government.