Effect of railgun electrodynamics on armature discard

An experiment was conducted to examine the role that electromagnetics plays during the sabot discard process. This investigation is less rigorous than an accuracy test but uses a number of performance indicators, including measured downrange magnetic fields, to quantify the effect on subprojectile performance. The test program consisted of two sets of shots with different armature current profiles. A muzzle switch, which closed prior to exit, was employed to tailor the current and armature acceleration profiles. The exit velocity was 1100 m/s for both profiles so as to maintain the same aerodynamic pressure loads during armature discard. The time rate of change of launcher and switch currents and launcher voltages were measured. In addition, the time rate of change of the armature magnetic field was measured downrange from the launcher. The residual magnetic field in the armature after exit produced no observable effect on the sabot discard process.