Yes.
Turning the inner part adjusts the fine elevation for zeroing, turning the outer part gives large, adjustments for range.  If you adjust the inner drum that adjustment will apply at all ranges/detents marked on the outer drum.

To adjust elevation on an H&K rear sight, you use a tool to hold the two spring-loaded detents inward to disengage them from the rear sight outer drum (the part with the four sight apertures). You then turn the outer drum in the correct direction to adjust the elevation; to the right lowers the POI, and to the left raises the POI. The reason for this is that the outer drum is THREADED ONTO the inner base, with a standard right-hand thread.

Once the sight adjustment is made, you remove the tool to allow the detents to re-engage the outer drum, turn the rear sight to the desired position for the range you are shooting at, and shoot a group to see if your adjustment was correct. Repeat as needed...

ETA: Turning the inner threaded portion of the rear sight base and turning the rear sight drum would both accomplish the exact same thing. Either way, you’re just moving the drum up or down on the threads to raise or lower the rear sight. It’s just a whole lot easier to do this by turning the rear sight drum!