And it gets downright chilly at 20-plus thousand feet in an um-pressurized aircraft. Five hundred rounds of the big Fifty, fired in controlled bursts in such drafty conditions is not likely to cause issues of metallurgical failure in such circumstances.

At sea-level, assaulting Tarawa in the tropics? Who cares about barrel-life?

The LVT 4 carried a 20mm Polsten with a drum feed and a couple of . 30 cal BMGs. If they survived the crossing of the coral shelf and the drive up the beach, it was a miracle of sorts.