Locking on to a projectile somehow?

[Ultamis]

Yeah,what Im trying to do is make the rocket launcher shoot a "tracker" by making the target distance really far and make it only lock onto my "tracker".I wanted to make the tracker attach to things,but as far as I know only proj's can be fired from a weapon and not just fall to the ground,so what I need to do is give the needle shard a hitbox...BUT that hasnt been done yet so is my idea screwed until someone finds a way to add hitboxes?

[xzodia]

adding hit box's is easy...just copy form another hlmt, but i seem to recall from my tests that they only work when the object is in use by a bipd

[Ultamis]

I want to see if by somethin attaching to a bipd it becomes lock-onable.