Abstract: Progressive burning propellant granules are prepared by a process in which the solvent-wet propellant granules are wetted with a mixture of burning rate deterrent and solvent. The burning rate deterrent penetrates the solvent-wet granules. After deterrent coating, the granules are dried to remove processing solvents initially present in the granules.

Abstract: A process is provided for deterrent coating of propellant compositions useful as gun propellant in which the propellant contains nitrocellulose, nitroglycerin and nitroguanidine. In the process strands of propellant containing processing solvents are coated with burning rate deterrent on the exterior surface of the strand only. The strands are cut and dried. The process reduces exposure of the propellant to heat by elimination of the preliminary drying step to remove processing solvents prior to deterrent coating. Ethyl alcohol is the preferred processing solvent.