Third Person shooter rotate weapon arm towards screen center - crosshair

I am trying to make my character behave like this..


I tried making my whole character rotate towards crosshair and it turns into a helicopter..

Tried with pose blending in animation graph with bone upperarm_r transformation and still failed..

Tried with Control Rig , also failed..

Can somebody help me by providing a tutorial or a blueprint screenshot for this?
I need the arm/whole character rotation to the camera`s line trace hit result to be smooth and not snappy..