Indeed. I’ll bet the friction from the surrounding air gets that shell purty damned hot. I wonder what the degradation to the outer skin is like by the time it gets to target? It must take a beating.
Long range trajectory is going to put it very high, very fast, the Paris gun trajectory topped out at about 140,000 ft.
These projectiles are not intended to have a warhead, so they can be built to withstand a lot of heat.