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This paper presents documentation of a scaling methodology. We first get an understanding of the operation of the full scale system. The shape of the current curve in figure 1 is similar to the output pulse required for a 20 MJ muzzle energy launch. We use this current waveform as input to a non linear, coupled, magnetic and heat diffusion model in one dimension for a cylindrical armature. The equations shown in figure 2 are solved numerically for the B field, current density, and temperature distribution through the armature cross section as a function of time. The current density and B field are used to calculate the body force distribution through the armature at any time, and the set back inertial load is subtracted from the body force to give a representation of the bulk stress distribution through the armature. This procedure is outlined in figure 3 with a simple current density and B field distribution, but the distributions solved for in the non linear model are used in actual calculations. We compare the armature temperature distribution to the output of 3-D transient magnetic finite element codes for a second method check and there is good agreement as seen in figure 4. Returning to figure 1, we see the predicted temperature and stress distribution at the time of first peak and the time of the last current peak. We would like to replicate these distributions in a subscale armature to see how the material behaves before the full scale design is pursued. In addition we would like to operate the model at the same velocity as the system because experimental data indicates the transitioning of armatures is related to their speed.