Ah, now that's getting somewhere with a concept. It's still not Vasudan at all IMHO, but at least it looks like less of a ball-and-stick and more like a turret. I'm still not liking the double barrels, even if they are connected, because they still translate when they elevate.
Now the older one, while not at all pertinent to this discussion, I'm assuming is being used to show me that two barrels can be stacked vertically and still rotate in a sane manner. However, what you're really showing is a case where the entire turret (as in the thing the barrels mount on or protrude from) rotates up and down. That's a very different construction. And you really need a better texture job (one that doesn't use 6 textures for one turret) for that one.