The operating conditions of future Electro-Thermal Chemical (ETC) guns will exceed the boundaries of proven high-power reprated switching technology. These systems will be required to operate at moderate repetition rates and high coulomb capability with a long lifetime and high reliability. Existing ETC laboratory testbed systems use either spark gaps or ignitrons as the main discharge switch to produce a single shot multi-megajoule 12-24 kV, 50-100 kA, 1-5 ms pulses. These switches are right for laboratory experiments because of their fault tolerance and engineering experience with high current discharges. Solid-state switching for ETC guns is feasible but not used for existing systems due to the relative complexity of stacking and driving series devices for voltage hold-off. However, solid-state switching technology offers the best alternative to meeting the future field system requirements for lifetime and reliability. ETDL has initiated an evaluation program to investigate SCRs, GTOs and MOS Controlled Thyristors (MCTs) for electric gun applications this includes Electro-Magnetic (EM) guns, coil guns, as well as ETC guns.