On the Hunter with a camera controlled turret on top and the military boat with the camera controlled grenade launcher turret the following happens:
1.Sitting in the turret spot of the vehicle.
2.Enter the camera view of the turret (make the turret view with cross hair full screen)
3.Hold the right mouse button as if you were zooming in while in normal soldier view right as you enter turret view.
4. For the rest of the current mission, that specific turret view and any others you do this to, get stuck in max zoom as if it's constantly trying to zoom.