Pulling down on it cocks the action. Pulling back the rear trigger till it clicks , sets the very lightly set front trigger. When the shooter is ready to shoot , a light touch on the front set trigger causes the rifle to shoot. The little scew between the triggers allows the front trigger to be set as light as the shooter wishes to have it. There is a point where if the screw is screwed in too deep , the set triggers can not be set.