Well, another question: would it be plausible to scale up the MG42 proportionally to fire a .50 caliber or 20mm round? The amount of required gear would be no problem, but I just need to know if it would need a power mount or if it could still fit on a tripod or pedestal mount.
Hmmm... depends on what kind of mechanism as to what size round can ultimately be handled.
How the bolt locks,
if the bolt locks (as IIRC, the MK-19 doesn't)... all these things have bearing on that question. The simple answer is just 'the heavier the construction, the better it works when scaled up.'