Nothing to do with punt guns or waterfowl, but just the boom of a heavy black powder charge. I have over the years seen several anvils shot. Tried it once myself with about a 98 b anvil. Was a bit conservative with my powder & only lifted it about 3 feet. I was in a "Hollow" nestled between two hills & she still echoed down the valley. At a local $th of July fireworks show we had an older gentleman who would shoot the anvil out in the middle of a footbal field every year. He would lift his around 8-10 feet. The most spectacular I ever saw it done though was at an antique tractor & engine show. They carried their anvils out into an open field away from the crowd & set her off. When that top anvil reached its peak it was a mere speck up in the air, hard to even see. Wen she came down it buried itself in the ground & would have to dug out. That was spectacular. I can definitely imagine the sound of that big punt gun going off over water.
