Test #1-- fail, due to the homemade gunpowder mixture not igniting.
Test #2 -- Using commercially manufactured black powder and factory made canon fuse!
The only homemade component is the canon itself, made out of a giant bamboo tube reinforced with rope. Two handfuls of rocks and stones are the projectiles.
RESULT: The rocks did fly at the Gorn target from about 20 feet away, but they were very low velocity. The back end of the cannon (the area not wrapped with rope) split open and released the pressure prematurely.
The rocks might've given the enemy a few minor bruises but nothing lethal, not even incapacitating.