Flashless powder

Du Pont Report (1944) Flashless Powder for Navy Cannon. NDRC/OSRD Report No. 3726. 

Investigations showed that the salts of other alkali metals are not so efficient in suppressing secondary flame as potassium salts. Fairly numerous experiments were carried out to clear up whether or not known antiknock substances, such as tetraethyl lead or nickel carbonyl prevent the development of a secondary flame. They proved to have no effect on its development. In practice, two methods for removing gun-flash may be employed, i.e. either a special flashless powder is produced, containing nitroguanidine or DNT and a small admixture of potassium sulphate,... 

Double base powders, i.e. nitroglycerine powders without a volatile solvent also include modem flashless powders containing nitroguanidine. 

Other patents of the interwar period include several that specified addition of substances rich in carbon, e.g. of powdered hydrocellulose, to obtain flashless charges. In the U.S.S.R. nitroglycerine powder was used in which a part of the nitroglycerine was replaced by aromatic nitro compounds. During World War II the most widely used flashless powder contained nitroguanidine (in Germany called Gudol powder). 

Other substances suggested for flashless powder instead of nitroguanidine included aminotetrazole which was, however, rejected due to its hygroscopicity, and methylene-urea. 

This classification is offered, not in any belief that it clarifies a matter which is otherwise difficult to understand, but because it directs attention to the various possibilities and displays their relationships to one another. Some of the possibilities correspond to powders which are or have been used in this country or in Europe, and which are sufficiently described for our present purpose if they are mentioned specifically. Others will be discussed at greater length in the sections, below, which are concerned with the absorption of moisture, with gelatinizing agents, and with flashless charges and flashless powder. All the possibilities are actually exploited, though not always separately. 

Flashless colloided powder containing nitroguanidine produces a considerable amount of gray smoke made up of solid materials from the decomposition of the substance. The gases smell of ammonia. The powder produces more smoke than the other flashless powders which are used in this country. 

Sheeline, Develop Flashless Powder For the 90mm Gun , PAIR 1479 (1944) 4) G. 

High explosives may be class d according to their physical properties as powdery, meltable, semi-meltable and plastic. Propellants may be grouped on the basis of chemical composition into gun powder and similar mixtures, nitrocellulose (single base) and nitroglycerine (double base) powders, With respect to their uses and some properties they are divided into black powder, smokeless and flashless powders, and rocket propellants. 

Solvcniless powder in Japan Flashless charges and flashless powders Smokeless powder with penthrite Smokeless powders containing nitroaliphatic compounds Smokeless powders for rockets Cast double base propellants Technology of casting Powder casting process Slurrying process... 

Explosives—Trinitrotoluene (TNT), pentaerythritol tetranitrate (PETN), polymer-bonded explosive (PBXN), Research Department Explosive (RDX) compositions, explosive D, tetryl, fulminate of mercury, black powder, smokeless powder, flashless powder, and rocket and missile propellants. 

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