Testing of gun barrel erosion by erosion bomb

Abstract

The properties of the propellants are one important factor that determine gun barrel lifetime. To be able to study the propellants influence on the wear of gun barrel have we built test equipment based on a standard closed vessel. In this equipment the combustion products and gases pass through two nozzles. The changes after firing in weight and bore diameter of the nozzle with smallest bore diameter are used as measures of wear. Three propellants, two double base propellant designed for use in 12.7 mm ammunition and one LOVA (Low Vulnerability) propellant designed for larger calibre has been tested. The amount of propellant in each firing has been constant, 50.0 g. To obtain wanted maximum pressure the bore diameter of the nozzle with smallest bore diameter have been varied. In addition have firings with opposite order of the nozzles been carried out. The majority of the testing has been concentrated on two 12.7 mm gun propellant candidates. Obtained results with respect to weight losses of nozzles and changes in bore diameter gave significant differences between tested propellants. The results demonstrate also that by having the nozzle with the smallest bore diameter closest to