  In the real world application of railguns, the launch efficiency is one of
the most important parameters. This efficiency directly relates to the capacity
of the electrical energy storage that is needed for the launch. In this study,
the rail/armature contact behavior for two different armature technologies was
compared. To this end, experiments using aluminum c-shaped armature and copper
brush armature type projectiles were performed under same initial conditions.
The c-shaped armature type showed a superior behavior with respect to
electrical contact to the rails and in acceleration. A 300 g projectile with a
c-shaped armature reached a velocity of 3100 m/s and an overall launch
efficiency including the power supply of 41%. This is to be compared to 2500
m/s and 23% for the launching of a projectile using a brush armature.
