Potato Shoulder Cannon
This is a very powerful shoulder-fired potato cannon, comparable to combustion-powered potato cannons. The purpose of the array of small pipes is to acheive high tank volume while preserving the high pressure capabilities of smaller pipe. This mess of pipe has earned this cannon the nickname "The Pitchfork of Doom."
By firing it directly upwards and timing how long it takes to hit the ground, I calculated the firing velocity disregarding air resistance. Then, a friend of mine generously offered to write a simulator program to factor in air resistance. (thanks K²!) Thus, the approximate firing velocity was found to be around 55 m/s (180 ft/s)