1. Pulsed power system to provide proper rise time to match armature transit time through the coils (rise times of order of 100 microseconds).
2. Control system to measure armature position and synchronize power system to armature
3. Power efficiency to minimize the size of power and thermal management systems
4. Thermal management of coils and power systems
5. Reduction and control of mechanical gouging in barrel at high speed
6. Cyclic stress fatigue in pulsed coils
Of the three EM gun concepts, only the railgun has demonstrated launch velocities in the
2 to 3 km/sec range. The coil gun may have potential, but it is far less mature than the
railgun. Very little effort has gone into developing coil guns, and in any case this approach
appear to lack the railgun’s war fighting or growth potential.
Source: Naval Electromagnetic (EM) Gun Technology Assessment,” J. Bachkosky, D. Katz, R. Rumpf, W. Weldon, United States Naval Research Advisory Committee (NRAC) Panel on Electromagnetic (EM) Gun Technology Assessment. NRAC-04-01, pg 45. http://www.onr.navy.mil/nrac/docs/2004_rpt_em_gun.pdf