AbstractSteady state detonation velocities have been measured in small brass‐confined pressings of PETN. These velocities were found to vary linearly with the reciprocal of the charge diameter and directly with the compact density. For a pressing density of 950 kg/m3the velocity at infinite diameter was calculated to be 5.27 km/s (50.02 kmk) and the Eyring‐type „reaction‐zone length”︁ 0.54 mm