Well, maybe.
Acid Arrow, for example, travels 400+ feet. There is no way you can throw anything that far (even in a fantasy world), so I would have no problem ruling that magic is propelling the Orb. Once it gets to the AMF, no more propulsion, it drops to the ground.
In fact, I have no problem ruling that although the Orb starts in your hand, it is not fully formed until it reaches the target. The Instantaneous of it is the same as the Instantaneous of Fireball (effectively). If you rule that Orbs get through, I suspect that you will have to rule that the bead of Fireball gets through as well (it just doesn't explode?).
But, it would be nice to find some rules support for a position that the magic is propelling the Orb.