I have seen a lot of shell art, I came across a decoracted wooden shell I had to buy. The seller said it was a sabot, and it stayed in the gun when not in use, and was later decoracted. I have researched it, and thought it was probably just a practice round that had been decorated with lots of nail heads and three bands of glued in paper with writings. I'll attach photos. It is about 13" tall, about 3.75" in diameter (around 90 mms), is made of wood with a few hundred iron nails with decoractive round heads. The best I can translate the top line is I think something like "German fear God and otherwise nothing in the world", the 2nd line is missing at least one word "???? ??nnerlling to the ????? time" and the third is almost completley missing stating in German "feder gespend???? ??????????"
I also picked up a French shell at the same time that appears to be decorated with the 81st Wildcat Division from the battle near Verdun in WW1. Let me know if you know anything about the shells, thanks, Ray.