The goal of the Cannon Caliber Program is to drive 185 g integrated launch packages to 1850 m/s. Three, five-round salvos with a firing rate of 5 Hz are intended to defeat specified targets at a range of up to 3 km. After an extensive alternative study, the design team consisting of United Defence FMC/BMY, the Center for Electromechanics at The University of Texas at Austin (CEM-UT) and Kaman Electromagnetics Corporation (KEC) has chosen to use an air-core, compensated pulsed alternator (compulsator) to power a rapid fire railgun to accomplish this task. A railgun launcher has been designed to fulfil the rapid fire requirements of the system just described. The design incorporates a directional preloading feature and ceramic sidewalls which combined make the railgun structurally stiff and lightweight. This publication focuses on the design, development and initial testing of the railgun launcher. >