We bought the barrel from an old rifle maker we know, the wheels were picked up at a junk store in Sevierville, TN. All the wood is red oak cut by a friend of mine who has a saw mill, he also machined the axle and wheel bearing. I built it in my garage, took about 2 weeks.
We shot it a few times this weekend just for noise. The bore is 3.5" we used a charge of 4 oz. of black powder, grass as wading and shot chalk and streamers. The Cannon never moved under recoil but made a great BOOM!