PaPa Peng wrote: : : Thanks for the answer. There is still the question of overheating. : It won't take too many rounds for the gun barrel to become red hot. : The tube metal expands, The tube diameter shrinks and that seizes the : round (as per overheated machine gun barrel.) What then? : I understand modern gun tubes are made with a process called "hydro swaging". Two telescoping tubes are used, the tube is filled with a fluid, the ends sealed, and the fluid is expanded.
The inner tube expands past its' plastic limit, and remains forever expanded to its current size. The larger outer tube does not expand past its' plastic limit, so it is constantly attempting to squeeze the smaller tube back to its original diameter.
Also, I doubt the tube diameter shrinks. At Waterloo, IIRC, the Kings German Regiment was frantically looking for oversize balls for their muskets at the farmhouse(?) they were attempting to hold. Same story at Rorke's Drift during the Zulu wars. (Actually, I believe the KGR were simply looking for ammo, period).
And, finally, I wonder how much heat a modern smooth bore gun tube absorbes? Without the friction of the rifling, it is probably not as much as a rifled barrel would generate/ absorb.
Bruce