The first 40 feet of the 10-inch-diameter barrel is schedule-80 steel, the stuff typically used for steam pipes and oil drilling. Five extensions of heavy-duty aluminum make up the total length, just shy of 100 feet. Bought from steel suppliers and bolted together by Arold and his construction crew, the extensions can be disassembled before transporting the cannon from one place to another. To prevent sagging, the barrel is supported by cable run over a 16-foot mast erected from the platform. As the pumpkin travels toward the barrel's mouth, it builds velocity, without being slowed down by the excess friction that a longer chute could create. Arold and Gill have achieved distances of 3,700 feet with pumpkins and broken a mile with a bowling ball. Pocked with the craters of landing projectiles, Gill's fields are now geological records of the shots fired. Except for the first bowling ball—that was never found.