Why "C" armatures work (and why they don't!)

While plasma armatures perform well at high velocities, they have severe effects on railguns at the shot start position. Solid armatures overcome this factor but perform less well as velocities increase. Many types of solid armature have been tried, including metal fibers and magnetic obturator types, but the classic "C" type remains the armature of choice for high-velocity projectile launches. The recovery of fired armatures at the Kirkcudbright range has allowed many of these ideas to be formulated. This paper looks at what happens to "C" types, explains the basic processes occurring as the armature gains velocity, and identifies the limitations of this design. It offers suggestions for improving performance, including materials and design options, with outline results in some areas, and offers some design characteristics to be considered with this classic armature shape. Comparison with alternative armature concepts is briefly made so as to present an overall view.