<p>The present study is focused on the reflection and transmission of a longitudinal elastic stress pulse at a discontinuity between two cylindrical bars subjected to impact loading at one end. Experiments were conducted to investigate the propagation of the longitudinal elastic stress pulse in the two cylindrical bars with discontinuities in the cross section and/or material properties using a split Hopkinson pressure bar setup, without a specimen. The reflection and transmission coefficients for stress and energy were investigated across a wide range of cross section and impedance ratios and compared with theoretical predictions from one-dimensional elastic wave theory. The accuracy of the measured reflected and transmitted stress pulses was verified by a two-dimensional axisymmetric dynamic finite element analysis. The applicability and limitations of one-dimensional elastic wave theory were discussed in terms of wave dispersion.</p>