An autocannon design that is extremely simplistic, and when I made it, I intended for the main structure to be placed below the surface. Anyway this thing sucks, flipping two directional levers (up-down, left-right) breaks the system, prompting you to go into the machine and fix it, flipping off a lever too fast can cause it to not stop moving, and you might need to reattach all of the pieces together when you place it.

Also, the ammo storage is located at the very bottom.
Additionally, I find it strange there's no 1.20.X versions, as the machine was made in that version category.