The Maschinengewehr (Schwarzlose) M. 7, also known as the Schwarzlose MG, is a medium machine-gun, used as a standard issue firearm in the Austro-Hungarian Army throughout World War I. It was utilized by the Dutch, Greek and Hungarian armies during World War II. It was routinely issued to Italian colonial troops, alongside the Mannlicher M1895 rifle.

Can we draw the following conclusion?
The Maschinengewehr got dirty.
It's impossible to say