It is 10ft long with a 2" dia. barrel and 4" dia.X5ft long resivoir.
The cannon uses Compressed Air for an energy source. The compressed air enters through the valve assembly and fills the rear chamber as well as the resivoir. Note the inlet for the air and the pipe connecting it to the cleanout plug.
When the hook is pulled upward the the air pressure from the rear chamber pushes the stopper out causing an almost instanteanous drop in pressure. The drop in pressure pushes the piston back that seperates the rear chamber form the resivoir. The piston pulles the plug from the 2" barrell allowing the air in the resivoir to rush into the barrel pushing out the potato.