Ballistite is a double-base powder used as a rocket propellant. It is composed of two explosive substances, nitrocellulose and nitroglycerin, blended together with diphenylamine, which acts as a stabilizer. It burns with a considerable amount of flash and smoke, and generates a great volume of gas. Ballistite burns progressively, but at a rate dependent upon the composition and physical characteristics of the powder grain, the temperature of the powder grain before ignition, and the pressure during reaction. It is produced in various shapes to fit the rocket motor housing.

Basically, solid propellant charges, such as Ballistite, may be grouped under one of two types- restricted-burning and unrestricted burning.

A restricted-burning charge has some of its exposed surfaces covered with an inhibitor to control burning. By this procedure, burning can be restricted to take place only on the desired surface or surfaces. Controlling the burning area in this manner lengthens burning duration and determines the combustion chamber pressure for a given charge. A burning cigarette is a good example of restricted-burning, if you consider the paper-covered portion as representing the inhibited area.

Unrestricted-burning charges are permitted to burn on all surfaces simultaneously. Relatively speaking, the unrestricted type of grain delivers a large amount of thrust for a short period of time, and the restricted type of grain yields a smaller amount of thrust for a longer period of time.