Solved
How the heck Spitfire and devotion are "light" machine guns!
Both are pretty much weapons for defending WW1 fortresses, but in respawn universe they are "light"!
In the real world these guns are considered 'light' machine guns. This is because they are 'light' enough to be used by a single person. A heavy machine gun would be something like you see mounted on top of a humvee.. typically shooting much larger caliber rounds than the LMGs.
