Abstract: A firearm cartridge case capable of withstanding internal gas pressures of at least about 50,000 psi has two substantially cylindrical portions of significantly different diameters interconnected by a frusto-conical shoulder portion. The case has a ratio of its overall length to its diameter, at a location 1.25 inch from its base, of no more than about 4.2, giving it an unusually short, fat profile. The base of the case has a rim with an outer diameter substantially no less than the case diameter at the aforementioned location, to facilitate reliable feeding of the cartridge from the magazine. The corresponding firearm chamber which matingly accepts the cartridge is capable of withstanding internal gas pressures of at least about 65,000 psi.

Abstract: A plurality of pressure transducers are spaced apart longitudinally along a mass of fluid so that they can sense disturbances in the fluid. A projectile launcher, which is typically a gun, is positioned such that the projectile launcher can be discharged to launch a projectile into the fluid. The pressure transducer(s) will sense the disturbance created in the fluid as the projectile passes through. A computer connected to the pressure transducers will process the output of the pressure transducers creating a response curve which is related to the energy dissipation of the projectile.

Abstract: An elongate vessel containing a fluid is equipped with at least one and preferably a plurality of pressure transducers spaced apart longitudinally along the vessel that can sense disturbances in the fluid. A projectile launcher, which is typically a gun, is positioned such that the projectile launcher can be discharged to launch a projectile into the fluid. The pressure transducer(s) will sense the disturbance created in the fluid as the projectile passes through. A computer connected to the pressure transducers will process the output of the pressure transducers creating a response curve which is related to the energy dissipation of the projectile.