The easiest to achieve that is to lower your interpolation speed. This would however cause your gun and character to trail after your crosshair. Which could give a more unique look to your game. It all boils down to your intended design. If not… I would go about having one interpolation speed for the common case, meaning just aiming, and one for when your Yaw transitions between the extremes (-90 to 90 etc). Best of luck (•ᴗ•)