The experiments of Menikoff et al on a projectile hypervelocity launcher using a fast shock tube (FST) are modelled using smooth particle hydrodynamics (SPH) technique. In a FST, the progressive detonation of a co-axial HE cylinder induces a cumulative shock in the liquid-filled core. This shock hits a thin flyer and accelerates it to hypervelocity. The comparisons are made on flyer velocity profile, peak pressure and shock speed in liquid core. The SPH reproduces the qualitative and quantitative aspects of the FST and is well-suited to the high strain-rate feature of this experiment.