An experimental program has been completed which provides secondary fragment impact sensitivity data for designers of munition production facilities. The targets tested were 155 mm, 120 mm, 81 mm, and 4.2 inch shells and two models of melt kettles. All target shells depicted the just filled condition of the loading operation where the Composition B or TNT is in the molten state. The data shows the threshold initiation conditions of fragment velocity and mass. The threshold conditions are shown to be strongly dependent on the degree of confinement of the explosive or the shell casing geometry. The ratio of the wall thickness to outside diameter is one of the pertinent parameters to correlate the casing geometry with the fragment velocity needed for initiation of the explosive system.