I'm selling a 2 3/8" cannon that shoots tennis ball projectiles. We fill the ball with lead behind about 8 tablespoons of blackpowder. The barrel is approx. 4' long with an overall diameter of 5 3/8". The walls are about 1 1/2" thick with a threaded and tapped plug that was welded on the breach. Always a crowd pleaser at family functions. Approx 7' long and 4' tall.