I'm trying to figure out how to remove the standard attack of a rifle, and instead use an "activate item" attack that has limited uses (like an energy shield).
I've tried everything I can think of but can't seem to find anything in my attack choices corresponding to the properties of the gun (the effects I tried were Kill, Frag Grenade, and cloak) or even anything in the on-self actions.

Basically I'm trying to create a rifle with consumable ammunition and multiple firemodes determined by the gun itself, not the feat used to attack. I'd like to apply different firing modes to different weapons. (Rifle uses Semi-Auto and Burst, similar effects as Sniping or Rapid Shot, but because of disabled feats power shot is not available)

Assuming this can actually work I'd like to find some way to "charge" the weapon back up without making it completely disposable.

Is there a simple way to do this that I'm just missing, or do I need 4 tutorials and a buttload of caffeine?

You could always just try to make the rifle use up some force points each time it shoots. BUt, of course, it would recharge over time. But isn't that realistic? When the force points are depleted, you could say the gun overheated. And when it restores, it cooled off. I am not good at this kind of thing, but it might work.