The essential construction features of a piston actuated shock tube are described, and its advantages relative to the conventional use of diaphragm ruptures for shock initiation are listed. Typical operational parameters are presented to illustrate the levels of reproducibility achieved. Tests with He and N2drivers into ∼99% Ar (1.0%–0.1% reagent) covered shock speeds from 1.539±0.002–0.8143±0.002 mm/&mgr;s, corresponding to 2390–847K incident shock temperatures. Application of this tube for recording postshock front density gradients of the endoergic dissociation of ethane and the exoergic condensation of iron atoms via the laser–Schlieren technique is described.