Recently, there has been significant interest in thermite reactions with nanoscale particles due to their high combustion temperatures and fast reaction velocities. However, the mechanism by which the reaction propagates is not well understood. In order to further understand the propagation mechanism for the Al/CuO nanoscale system, experiments were conducted whereby reaction velocities for various mixtures at different pressures were experimentally found. In the first set of experiments, the sizes of the metal and metal oxide particles were varied between the nanometer and micron scale and the combustion velocities were compared. In the second set of experiments, the combustion of the nanothermite was examined at various pressures in an argon atmosphere. The data indicates that the increased flame propagation speed is significantly more sensitive to the CuO rather than the Al particle size. Furthermore, it is shown that there is a slight increase in propagation speed when increasing from 100 to 180 psig, followed by a significant drop-off in propagation speed at higher pressures.