Manual Reload Script - Different approach
I am aware that manual Reload mod already exists. It blocks auto reloading when gun is empty. And uses a custom empty magzine clicking sound which comes bundled with the script files.
Can this be achieved by making the game think that
Empty Mag = Empty Mag + No reserve Ammo
(Untill you press Reload button)
This way, the game will itself play the Empty Mag clicking sound.