We have investigated some of the problems involved in switching fast, high‐power pulses using single‐turn saturable core inductors constructed of Metglas 2605SC. These include hold‐off voltages and times, output pulse risetimes, B‐H curves of the material under fast pulse conditions, and propagation of the saturation field through the core. Experiments were done at Sandia on the RAMSES I accelerator which uses a 200‐kV Marx generator to provide a 200‐ns pulse to a 1 &OHgr; coaxial water transmission line.