this cannon can shoot 8 pieces of TNT 150 blocks without any Bullet/TNT drop!
that's right it can shoot TNT through a 1 block gap at least 25 blocks away from the target.
This was made as a response to Mumbo's "Making the SILLIEST TNT cannons in Minecraft" video, here's the link:
https://www.youtube.com/watch?v=ZFlA0W8DGXY
he didn't provide a tutorial or a world download so I built this so people can use the. as I call it, Laser cannon yourself.
Hope you enjoy.

CHANGELOG

V1.1: added more firepower and a place to view the dirt disappear
V1: uploaded original Laser cannon