The material or fragment discharge is controlled by means of a device (4) in connection to the triggering, such as by means of an initiation charge (5), of the main charge (3) in the ammunition unit (1). The liner is devised as being exposable for effect from the explosive charge or charges (6) that are devised as being able to be initiated upon or shortly prior to the triggering of the main charge. The explosive charge achieves, upon initiation a pre-deformation of the liner (4) prior to the liner being affected by the triggering of the main charge for the material or fragment discharge The fragment forms can be rendered more effective in relation to design solution known by prior art by means of the choice explosive charge form and placement.