Erosiveness of smokeless powder

Every powder produces erosion or bore wear to some extent. After a large number of shots the wear may be considerable, especially in large guns, and this reduces their accuracy. The erosiveness of a given powder depends, first of all, on its flame 

Vieille [11] conducted extensive experiments on erosion in a manometric bomb, closed except for a small orifice, about 1.3 mm dia. in a metal plug (Fig. 192). Hot gases escaping through the orifice, eroded it to an extent determined by weighing the plug before and after each experiment the loss of weight was taken as a measure 

The erosion of metals varied depending largely on the melting point. For various metals erosion expressed in mm3 of metal removed from the orifice per 1 g of powder was  

Vieille considered that erosion is caused by fusion of the metal and subsequent expulsion of the molten substance. The results of Vieille s experiments are summarized in Table 170. The weak erosive action of nitroguanidine, attributable to its low temperature of explosion, is noteworthy. 

Apart from physical agents such as temperature and the mechanical action of gases, chemical agents also cause the erosion. Monni [50] noticed that the erosiveness of smokeless powder decreases with the addition of charcoal, probably because the additional quantity of carbon thus introduced serves to carbonize the steel which may undergo decarbonization under the influence of C02 at a high temperature, according to the reaction  

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