IMO, No. I have only leveled to 30 as Gunnery and using Grav Round is more efficient overall. Most of the talents either reduce the cost, double the debuff, or proc ammo for Grav Round alone. When I do any certain rotation, I only use Grav Round, Full Auto, or Impact Bolt.
Charged Bolts is roughly 100+ less damage at 30. I think its more of a replacement for other specs like Combat Medic that don't have access to it.