Cartridges completely combustible

The modern cartridge evolved over this period to a very high standard of reliability. Ironically, serious attempts by reputable large munitions companies are now being made to perfect a completely combustible cartridge and/or caseless ammunition which would be suitable for use in modern firearms.28... 

Under the term Vzryvchatyiye veshchestva v predokhraniteTnoy obolochke (Explosive substances in protective envelope), sheathed expls have been used in Russia. There are two types of sheaths inert sheath which consists of Na bicarbonate with or without Na chloride and active sheath which consists of Na bicarbonate with ca 10% NG incorporated. The active sheath has the advantage of being pulverized completely on expln of enclosed cartridge, thus filling the mine atmosphere uniformly with non combustible dust (Ref 6, p 514)... 

As the breech mechanisms of present guns are not designed to achieve complete sealing off the gases of combustion(complete obturation), the base of combustible cartridges should be made of a non-combustible material. This material can be either metal(brass or steel) or a noncombustible plastic. Obturators prepd from polyethylene are described in Ref 13-Cartridges prepd by these methods are known as partially combustible(Rei 15)... 

For simple air filter duties, without silencing, the cartridge may itself form the complete filter. This sort of design would be used primarily as a crankcase breather filter, or a filter on a hydraulic reservoir breather. It may also be used as an intake filter on very small internal combustion engines, because of its simplicity, low cost and low pressure drop. The complete filter is then replaced as a unit when clogged. 

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