Abstract: The Finnish Defence Forces have implemented a surveillance system for gun propelling charges utilizing conscript practice troop firings. In this study the muzzle velocity data collected during troop firings of a 155-mm weapon system have been statistically evaluated. The elimination of the first round fired of each series of collected muzzle velocity data was found to reduce the variation in the data. For one charge zone, the study determined a need to verify the validity of standard muzzle velocity values in the firing tables. The muzzle velocity data collected in conscript troop firings were found to be suitable for the estimation of lot-to-lot and gun-to-gun variances if the data is not too unbalanced. The methodology for identifying and removing erroneously marked observations and outliers in the muzzle velocity data collected by conscripts has been developed and the evaluation of the results connected to each studied charge lot/zone has been conducted. The muzzle velocity data collected was found to be usable for numerous purposes, as long as the characteristics of the data are taken into consideration.