Use a Pawn class instead. A character will give you a headache. It will fight you. And it is likely to win, just grind you down. 
A pawn like this would give you some controls out of the box, and none of the fuss:
A character is great if you have arms, legs and bi-pedal movement. A human form.
Does this Begin Play trigger:
Perhaps it’s important for us to know how the new cannons are added? Do you Set Class on CAC or use some other way?
Btw, there’s also a way to get what you need without using CACs which are, generally, horrible to work with. Not sure how far you’ve got with the progress.