2D gun aiming problem

Hi, I'm working on a 2d game where the player holds a weapon and aim /flip with the cursor. When the player is flipped, the rotation / aiming with the mouse isn't fluid anymore, the player is not able to do a full range of rotation. Can someone help me with that ? See script below [Weapon Controller Script][1] [1]: /storage/temp/191737-weaponcontroller.txt