Abstract: Working principles of a setback-shock simulator for explosive loadingare studied in this paper. The interreaction between the weight hammer and theexplosive sample is analysed making use of the stress wave theory. It has beendiscovered that the action of initial shock wave is not important in the loadingand unloading history. Based on the theory of rigid body dynamics thisinterreaction is simplified as a second order system and a set of equationsrelating to stress, stress rate and stress pulse width are derived. The results ofanalysis fit well with experimental data. This study will be of benefit to thedesign and adjustment of such simulators and to the analysis of experimentalresults.