When you have ammo in your gun, and you are able to shoot out the rounds, you can see your character pulling the trigger.

If you are out of bullets, and you try to shoot, you can hear the sound of the gun trying to fire as if your character was pulling the trigger. But the problem is that he's not pulling the trigger, which he would have to be doing to have the gun attempting to fire.

There needs to be an animation that shows the character pulling the trigger even if the gun has no ammo.