Custom Collision Channel

I have a projectile set up and have been working my way around having the actor colliding with the projectile from the start. However that method is more than like going to get costly. As In I had it ignore everything mostly and when it collided with an actor (which is a hit box with a cube that I turned on and off to get an idea of the size) it would set off all these events and eventually die. However doing that for everything would get tedious for a fact. All I need to do is avoid it hitting the player at the start of the spawn for the projectile. It can fly off like it should but half the time it flops to the ground like a dead fish.

This may not normally be an issue for most people but I have other hit boxes and such attached to him which also registers I think as a hit box.

Anyways I have been hunting for just ignore x actor but all I got was when it was moving which did nothing. I eventually ran across custom collision channel and all I got was how to make it and nothing else. I am curious as to how do you assign it to an actor and its children.

(I really would like the projectile to ignore the player and hit everything else so I do not have to plaster the killing actor everywhere.)