I'e seen this weapon in at least one other picture (related to Strike Witches) and labelled it a machine_gun, since I'm quite sure I read a reference to it as such in WWII articles. But since I'm not 100% certain, I'd like to get corroboration.

I don't know about guns, but I do know Eila's familiar is a black fox, and not a wolf. Changing back the tags.

Well, it supposed to be either MG34 or MG42. Ignoring some artistic inaccuracies, I think it safe to tag it as machine_gun.