Propellants gun

W. A. Blaine and co-workers, "Detonation Characteristics of Gun Propellants," preprints of 9th Symposium (International) on Detonation, Portiand, Oreg., Aug. 1989, p. 233. 

P. Benhaine and co-workers, "Investigation on Gun Propellant Breakup and its Effect on Interior BaUistics," in Proceedings of 4th International Symposium on Ballistics, Oct. 1989. 

S. Iyer and co-workers, "New High Energy Density Materials for Propellant AppHcations," in 5th International Gun Propellant and Propulsion Symposium, ARDEC, Picatinny Arsenal, N.J., Nov. 1991, pp. 18—21. 

Gun Propellents. Although the stresses on individual gun propellant grains are less severe because of the small size, these propellants must withstand much higher weapon pressures and accelerations. Formulation options are usually more limited for gun propellants than for rocket propellants because the products of combustion must not foul or corrode a gun, should have a low flame temperature, and should exhibit minimum flash and smoke characteristics. Gun propellants are examined microscopically for porosity, are tested for mechanical characteristics, and fired in closed bombs to determine the burning characteristics. 

Table 4. Thermochemical, Thermodynamic, and Performance Characteristics of Nitrocellulose Gun Propellants ...

Experimental Determination of the Burning Rate. Experimental determinations of the burning rate are made with the closed tomb for gun propellants and the strand burner for rocket propellants. The closed bomb is essentially a heavy-wahed cylinder capable of withstanding pressures to 689 MPa (100,000 psi). It is equipped with a piezoelectric pressure gauge and the associated apparatus requited to measure the total chamber pressure, which is directly related to the force of the propellant. It also measures the rate of pressure rise as a function of pressure which can then be related to the linear burning rate of the propellant via its geometry. Other devices, such as the Dynagun and the Hi—Low bomb, have also been developed for the measurement of gun propellant performance. 

Fig. 2. Effect of grain shape on surface exposed during burning of gun propellants. Cross section of grains are shown.

Gun Propellents. Low sensitivity gun propeUants, often referred to as LOVA (low vulnerabUity ammunition), use RDX or HMX as the principal energy components, and desensitizing binders such as ceUulose acetate butyrate or thermoplastic elastomers (TPE) including poly acetal—polyurethane block copolymers, polystyrene—polyacrjiate copolymers, and glycidyl azide polymers (GAP) to provide the required mechanical... 

All five processes requite plasticization of the nitrocellulose to eliminate its fibrous stmcture and cause it to bum predictably in parallel layers. Mechanical working of the ingredients contributes to plasticization and uniformity of composition. The compositions of representative nitroceUulose-based gun propellants are shown in Table 7. 

Black Powder. Black powder is mainly used as an igniter for nitrocellulose gun propellant, and to some extent in safety blasting fuse, delay fuses, and in firecrackers. Potassium nitrate black powder (74 wt %, 15.6 wt % carbon, 10.4 wt % sulfur) is used for military appHcations. The slower-burning, less cosdy, and more hygroscopic sodium nitrate black powder (71.0 wt %, 16.5 wt % carbon, 12.5 wt % sulfur) is used industrially. The reaction products of black powder are complex (Table 12) and change with the conditions of initia tion, confinement, and density. The reported thermochemical and performance characteristics vary greatly and depend on the source of material, its physical form, and the method of determination. Typical values are Hsted in Table 13. 

L. S. Lussier and co-workers, "The Use of Thermodynamic Codes for Comparison of Propellant Performance," in Tifth International Gun Propellant... 

K. Adas, A. Method of Computing Web for Gun Propellant Grains from Closed Bomb Burning Rates, memo report 73, Naval Powder Factory, U.S. Navy, Indian Head, Md., 1954. 

T. E. Goddard, "The Euture of Bulk Loaded Eluid Propellant Guns," in 3rd International Gun Propellant Symposium, American Defense Preparedness Association, Washington, D.C., Oct. 1984. 

D. Mueller, Procedures for the Production of Gun Propellant by Use of Different Extruders, Erauerhofer Institute fuer Treb-und Explosivestaffe, Pfinztal-Berghausen, Germany, June 1982. 

D. Mueller, "The Continuous Processing of Gun Propellants by the Twin Screw Extmder," in Proceedings of the Third International Gun Propellant Symposium, Dover, N.J., Oct. 1984. 

C. Boyers and K. Klager, eds.. Proceedings of Symposium on Propellants Manufacture, Hazards and Testing, American Chemical Society, Washington, D.C., 1969. Gun propellants... 

Gun propellant and compressed gas are the most widely used energy sources. In single-stage, compressed-gas systems velocities can be achieved from perhaps 30 ms to 1.5 kms These compressed-gas gun systems are the most widely used as they are quite safe and can be incorporated into typical university and industrial laboratories. A typical compressed-gas gun experimental configuration is shown in Fig. 3.5. 

US Army gun propellant and rocket propellants to support and advise field surveillance activities of the safe life potential and/or possible degradation of both bulk stored material and items using these propellants -... 

New Gun Propellant , AFATL-TR-70-45, Hercules Inc (Cumberland, Md) Contract F08635-69-C-0164(1970)... 

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