A project has been running for the past years to define a route to assess the safety of UK explosives. To this end, a series of plate impact experiments have been undertaken in order to characterise the unreacted Hugoniot of a UK castable plastic bonded explosive (RF‐38‐22). A second programme, using embedded particle velocity sensors, has been undertaken to investigate the shock to detonation transition (SDT) in the PBX. The experimental facility is described, the techniques used are discussed, and results obtained are reported. The data obtained has been used to calibrate a hydrocode model for SDT based on viscoplastic ignition and subsequent grain burning with pressure‐dependent kinetics. This model is described, and results of calculations are presented.