The driving configuration for a drug delivery device comprises an energy storing member (2) providing a force suitable for driving a bung (1) arranged in a container (3), the bung being movable relative to the container. The energy storing member (2) is loaded by an alteration of its mechanical state with respect to a mounting element (5), which is relocatable in such a manner that a force provided by the energy storing member when it is loaded is reduced by a relocation of the mounting element.