Performance ballistic

Sansom, Evaluation of Ballistic Performance of Commercially Available Transparent Armour , Rept No MRL-TN-385, Maribyrnong (Australia)... 

The burning rates of standard aluminized hydrocarbon binder composite proplnts may be increased significantly not only with ferrocene derivatives but also with compatible carborane-type burning rate additives. However, most ferrocene derivatives are volatile solids or liquids which have a tendency to evaporate from the proplnt during storage, thereby degrading ballistic performance. Rudy (Ref 71) minimized this problem by the use of polynuclear ferrocene... 

The above estimate at least partly explains why early 12-bore gun cartridges, containing 82 grains (5.3 g) of black powder, could alternatively be loaded with 26 grains (1.7 g) of double-base powder to give similar ballistic performance. 

High and Low Temperature Tests for Small Arms Ammunition. The purpose of these tests is to determine the effect of high (as high as +165°F) or low temperature (as low as -70°F) storage upon the ballistic performance of ammunition, or components thereof... 

Some TNT-based formulations have been tailored, made and tested for sensitivity and ballistic performance. When TATB, DINGU and nitroguanidine (NQ) are incorporated in these formulations, they become IHEs. Further details of these formulations are available in the literature [176]. 

The major ballistic performance parameters of a gun propellant are its energy expressed in terms of force constant and burning rate coefficients a, P and ]. 

Higher calorific value compared to HTPB and therefore better ballistic performance. 

Absorption or migration of nitroglycerine (NG), stabilizer and plasticizer from propellant to inhibitor should be as less as possible so that the physical properties and ballistic performance of the propellant during its storage are not adversely affected to the extent of vitiating their serviceability. 

The chief problem in the manufacture of polyurethane propellants lies in determining the point where the liquid, uncured propellant is reduced to the uniform consistency necessary to obtain reproducible ballistic performance. 

D. Vet Rolling. Since the ballistic performance of a proplnt depends to a great extent upon the thickness of the web of the grains, it is important to have it as uniform as possible. As it is difficult to prep all the balls of exactly the same diam, the simplest way would be to select a batch with si larger grain diam than required and then... 

A very important application of the heats of reaction is the calcn of the reaction temp of propints which determine in part the ballistic performance. Heats of reaction also permit the calcn of the adiabatic reaction temp of pyrot reactions which are of value in judging the luminous yield of flares as well as the heat output of thermite reactions... 

The manufactured 90 mm x 90 mm x 10 mm three-layered B4C/B4C-30wt%SiC tiles were tested as armor [67], The photographs of the experiment set-up of the ballistic test as well as a residual impression in the clay box that was used as one of the criteria in the ballistic performance of laminates are shown in Fig. 7.17. The ballistic penetration tests were performed to evaluate the ballistic performance of the laminates. Depth of penetration tests were used to evaluate the ballistic performance of the composite laminates. In addition, pure B4C monolithic ceramics were used as a standard for the test. Test panels were made using the three-layered B4C/B4C-SiC laminate and B4C monolithic ceramic material as the hard face. While the B4C monolithic tile had 100% of its theoretical density, the three-layered B4C/B4C-30wt%SiC laminates had about 3-4% of porosity. A commonly used Spectra fiber-reinforced polymer composite was used as backing plates. The targets were mounted on clay and the projectile was shot at the target at a specific velocity. 

The design of the test panels was selected to ensure defeat of the threat. The depth of penetration of the projectile into the backing was measured by peeling of the unpenetrated layers of the backing plate, and the diameter of the impression on the clay after the projectile had been shot was used to evaluate the ballistic performance of the laminate composites. The results of the ballistic performance evaluation are shown in Fig. 7.18. As one can see there was no significant difference in penetration of the projectile into pure B4C monolith ceramics and three-layered composite. 

Ballistic performance results (a) fraction backing penetrated (b) clay deformation. 

Consistently achieve the required ballistics performance even under very different climatic conditions. 

Black powder can vary from brand to brand. Variations in percentage compositions between manufacturers are small, but different charcoals, types of saltpeter (purity), different moisture content, and so forth can result in different ballistic performances from basically similar mixtures. Owing to a temporary shortage of potassium nitrate during World War I, sodium nitrate was used as a substitute. Ammonium nitrate has also been used as a substitute for potassium nitrate. 

Information obtained from visits to various munitions factories suggests that manufacturers will use whatever is available at the time, from whatever source, to complete an order, provided that it meets the required ballistics performance and produces no residues that are injurious to the gun. During the war years, shortage of material meant many variations in materials used in manufacture. For these reasons it is unwise to make assumptions about ammunition components and composition, even for the same caliber and manufacturer, as they could vary from batch to batch. The differences between ammunition with the same head stamp can be seen in Table 21.3 for Winchester Western in. 38 Special and. 357 Magnum calibers and in Figure 21.2 for. 30 Ml caliber VE 54 FI and VE 2-61 S. 

As a rule, studies of powder in the pressure bomb are carried out in comparison with a powder of known ballistic performance. They are very useful both in the development of powders and in production monitoring. 

The propellant grains will agglomerate whereby ignition will suffer. The same disadvantage may be caused by crystalline separation of stabilizers. The ballistic performance can also be affected. 

The ballistic performance of these materials was determined by a standard projectile impact test. This performance is characterized by the average impact velocity at which the projectile barely penetrates the test specimen. Accordingly the higher the characteristic velocity, the better is the ballistic performance or the ballistic impact resistance of the specimen. The data are presented in arbitrary units. 

The first and common description of the explosive performance is the detonation velocity D (measured at a desirably high charge density). This is not sufficient as resulted by our own research on light-element explosives (ANQ, TAGN), which exhibited besides attractive D values only low ballistic performance not predicted by model calculations. So as a second base is applied the Gurney energy JIEq. For a more profound analysis we recommend the brisance of an explosive which can be quantified by the depth (or the volume) of the denting from a detonation on a steel plate, the Plate Dent Test. 

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