The ADS doesn't display right, it only seems to happen consistently with the faction chain guns as far as I have been able to tell so far, but occasionally it will also happen any weapon (including pistols). It shows as basically a zoomed in hipfire and sometimes when switching back to hipfire it makes your character hold the gun at a really low position. kind of weird.
Specifically I am talking about the lasher. In the live game you look directly down the sights, on the test server it stays in hipfire position and just zooms in a little bit.