Particle size distribution of three batches of Hercules-supplied HMX were analyzed. The sizes were determined by the specified sieve analysis having a nest range of 180 through 10 ..mu... These sieves were used to comply with Hercules requests; they are also those customarily used for HMX qualification. Five analyses for each batch were performed on the material >10 ..mu.. and duplicates analysis for the <10 ..mu.. material.