The geometry and other properties of a repeating crossbow was optimized in order to maximize the output power. This article focuses mostly on the geometry of the 3-bar mechanism that distinguishes repeating crossbows from traditional crossbows but describes a model set up to be scaled for additional optimization with greater dimensionality. An optimization method was chosen that fits the problem and code is provided to demonstrate how this optimization was done to receive the reported results. While the results did not improve upon existing repeating crossbow power output, with adjusted constraints, it is believed that a fully optimized design can be found based on this work.