A gas gun for plane and shear loading of inert and explosive targets

The design and construction of a 75 mm bore laboratory gas gun capable of velocities up to 500 m s(-1) is described. The performance of the gun is compared with the analytical interior ballistics model of Pidduck and Kent [A. E. Seigel, Report No. AGARDograph 91 (1965)]. The gun is constructed for two idealized loading geometries. One is plate impact, in which the loading is in one-dimensional strain, accomplished by impacting plane impactors onto targets aligned to micron tolerances, precisely normal to the impact axis. Another is pressure-shear in which the target and impacting plate are angled, but still aligned to the same tolerances. The system requires flexibility for addressing the problem of reactive targets when design must allow complete detonation of the target (up to 250 g). This has been accomplished and the system approved for use by the appropriate authorities. (C) 2001 American Institute of Physics.