The Ventral gun can shoot higher then the iron sight and the bay opening would suggest.
I noticed something amiss in checking it out offline. I set .target and flew due south. Using the ventral gun, I was actually able to kill shoot myself in the process while changing view to watch the hit sprites on the target climb higher then the center of the target.
I don't know if it's the iron sight view or the gun limits causing it. I'm hoping it's both so the gun can be use vs a bandit dead six.