RU2584284C2 - Charge for 7,62(53 mm sporting rifle cartridge - Google Patents

Abstract

FIELD: weapons and ammunition.

SUBSTANCE: invention relates to throwing charges for small arms and can be used for charges to sports rifle cartridge of 7.62 mm calibre. Charge for 7.62×53 mm sports rifle cartridge of spherical powder arranged in the case with primer cap is made of spherical double-base powder with bulk density of more than 1.0 kg/dm³, phlegmatized olygoesteracryclate MGF-9 and centrate I, having in composition of nitrocellulose with nitrogen oxide content 213-214 ml NO/g, nitroglycerine 19.0-21.0 wt%, diphenylamine 0.3-0.5 wt%, moisture 0.2-0.4 wt%, ethyl acetate 0.01-0.1 wt%, coated from surface with graphite 0.1-0.3 wt% with following ratio of fractions wt%: (1.25-0.7) mm not less than 80, more than 1.25 and less than 0.7 of not more than 20.

EFFECT: invention provides reduced scattering of bullets and, consequently, high accuracy of fire.

1 cl, 1 tbl, 5 ex, 1 dwg

Description

The invention relates to the field of development of charges for small arms cartridges and can be used for charges to a sports rifle cartridge of 7.62 × 53 mm caliber.

Special requirements are imposed on sports weapons to ensure high firing accuracy, as estimated by the amount of dispersion. When firing a sports weapon, the dispersion of bullets occurs on an area whose borders can be taken as a circle. It is enough to measure the diameter of the circle containing all the holes (points of contact). It is allowed to evaluate the dispersion with the radius of the circle of dispersion of bullets containing the best half of their hit R50 or all 100% of the holes (R100). The magnitude of the dispersion of bullets during firing for rifled weapons is determined by the distance between the centers of the most distant holes from the group of shots at the target at a distance of 300 meters (dispersion diameter P _cf. ).

A patent is known [1] for a charge for a 7.62 × 53 mm sporting rifle cartridge, comprising spherical powder fractions containing centralites I (C I) and dinitrotoluene in the surface layer of grains, while in order to improve ballistic characteristics it contains powder with a bulk density 0.960-0.997 kg / dm ³ , and the content of centralite and dinitrotoluene in the surface layer of grains is 3.0-6.0 and 3.0-5.0%, respectively, with respect to the mass of gunpowder and additionally contains 0 in the surface layer of graphite 1-0.3 wt. %, with a residual moisture content of gunpowder 0.2-0.4 wt. % at the following content of fractions, in wt. %:

0.40-0.56 mm 50-75 0.56-0.63 mm 20-45 other fractions no more than 5

Also known patent for charge [2] (prototype) for 7.62 mm sports rifle cartridge made of spherical powder, made of nitrocellulose with a content of nitric oxide of 213-214 ml NO / r, carbon and diphenylamine, with a bulk density of gunpowder 0.960-0.990 kg / dm ³ . The content of centralite I and dinitrotoluene in the surface layer of grains is 3.0-6.0 and 3.0-4.5 wt. %, respectively, in relation to the mass of gunpowder, and additionally in the surface layer contains graphite in an amount of 0.1-0.3 wt. % and ethyl acetate in an amount of 0.5-1.2 wt. % with a moisture content of gunpowder 0.3-0.9 wt. %, with a mass ratio of fractions,%:

0.4-0.56 mm 55-68 0.56-0.7 mm 27-40 more than 0.7 and less than 0.4 mm no more than 5

The use of such charges in the 7.62 × 53 mm Sport rifle cartridge Extra does not meet the requirements for bullet dispersion characteristics.

The objective of the invention is to reduce the dispersion of bullets and, as a result, increase the accuracy of shooting.

This object is achieved in that the charge for a 7.62 × 53 mm sporting rifle cartridge, including spherical powder, placed in a sleeve with an igniter capsule, characterized in that the charge is made of spherical dibasic powder with a bulk density of more than 1.0 kg / dm ³ , phlegmatized from the surface of 3.5-5.0 wt. % oligoester acrylate MGF-9 and 3.5-5.0 wt. % centralite I in relation to the mass of gunpowder containing nitrocellulose with a nitrogen oxide content of 213-214 ml NO / g, nitroglycerin 19.0-21.0 wt. %, diphenylamine 0.3-0.5 wt. % moisture 0.2-0.4 wt. %, ethyl acetate 0.01-0.1 wt. % coated from the surface with graphite 0.1-0.3 wt. % in the following ratio of fractions, wt. %: (1.25-0.7) mm - not less than 80, more than 1.25 and less than 0.7 mm - not more than 20.

In FIG. 1 presents a view of 7.62 × 53 mm sporting rifle cartridge "Extra".

The cartridge consists of a bullet 1 and a sleeve 2 with an igniter capsule, in which a charge of a dibasic spherical powder 3 is placed.

The charge in the cartridge should provide ballistic characteristics: the average value of the maximum pressure of the powder gases is not more than 3000 kg / cm ² , the maximum value of the maximum pressure is not more than 3200 kg / cm ² , the difference between the highest and lowest values of the maximum pressure is not more than 350 kg / cm ² , the average speed of a bullet at a distance of 25 m in a group of 10 shots is 735-750 m / s, the dispersion of the speed of the bullets is not more than 20 m / s, the loading density is 0.80 g / cm ³ .

The authors found that the use in the charge of the proposed dibasic spherical gunpowder with a bulk density of more than 1.0 kg / dm ³ provides a diameter P _sr of bullet dispersion <7 cm.

The authors also found that the use of MGF-9 oligoester acrylate and centralite I as a phlegmatizer of gunpowder provides the necessary progressive combustion of powder elements. The decrease in MGF-9 and C I less than 3.5 wt. % leads to an increase in the pressure of powder gases in the channel of the barrel of the weapon and the deterioration of the progressiveness of gas formation, and an increase of more than 5.0 wt. % increases the mass of the powder charge and reduces the speed of the bullet, due to the reduction of energy saturation of the powder due to the large number of inert substances.

Diphenylamine (DFA) in the composition of gunpowder is used as a stabilizer of chemical resistance. The decrease in DFA less than 0.3 wt. % reduces the chemical resistance of the powder, and an increase of more than 0.5 wt. % leads to a decrease in the energy characteristics of gunpowder.

Ethyl acetate (EA) and moisture in the composition of gunpowder are inert components used in the manufacture of gunpowder by water-dispersion production technology and must be removed from the composition by drying the gunpowder. However, to ensure manufacturing safety, the residual moisture in the powder should be in the range of 0.2-0.4%. An increase in moisture of more than 0.4% leads to a decrease in the energy characteristics of the powder and, consequently, to an increase in the mass of the powder charge with a simultaneous decrease in the flight speed of the bullet due to a decrease in the energy content of the powder.

Graphite grade S-1 is used for surface treatment of gunpowder, which provides satisfactory flowability of gunpowder and reduces electrification. The decrease in graphite is less than 0.1 wt. % leads to a decrease in the flowability of gunpowder and an increase in electrification and, as a result, to a decrease in bulk density, and an increase in graphite of more than 0.3 wt. % leads to the formation of free carbon, i.e. there is no sustainable coating of powder elements.

Cellulose nitrates and the additive - oligoester acrylate MGF-9 serve as a high-energy base and provide mechanical strength, increased density of powder elements and, as a result, the required ballistic characteristics.

Table 1 shows the physico-chemical and ballistic characteristics of the spherical dibasic powder for a 7.62 × 53 mm rifle cartridge made within the boundary conditions (example 1, 2, 3), outside them (example 4, 5), as well as spherical gunpowder made by a known composition (prototype).

From the data in the table it follows that the spherical powder developed by the authors for a 7.62 × 53 mm cartridge ensures compliance with the requirements for bullet flight speed V _{25 cp} , dispersion of bullet flight speeds ΔV ₂₅ , dispersion cross-section size and powder gas pressure P _{max sr} in the gun barrel (example 1, 2, 3). The mass of the powder charge is in the range of 3.50-3.60 g, which ensures its loading density Δ = 0.8 g / cm ³ . The average flight speed of bullets V _25sr is in the range of 735-750 m / s with an average value of the maximum pressure of the powder gases in the barrel of the weapon, not exceeding 2900 kg / cm ² .

Outside the boundary conditions, spherical powder (example 4, 5) does not satisfy the ballistic characteristics.

Spherical gunpowder made by a known method (example 6 is a prototype) does not provide ballistic characteristics both in terms of bullet speed V _25cp and in terms of the maximum pressure of powder gases in the barrel of a weapon P _{max cf.}

Thus, the charge developed by the authors from spherical gunpowder for a 7.62 × 53 mm cartridge provides the required bullet flight speed V _25av - 735-750 m / s with a nominal value of the maximum pressure of the powder gases in the barrel of the weapon, not exceeding 2900 kg / cm ² , and the average value of the dispersion cross-section P _sr is 4.2-6.5 cm with a norm of not more than 7 cm.

Information sources

1. RF patent No. 4942294, MKI F42B 5/16.

2. RF patent No. 2448932, IPC F42B 5/16.

Claims (1)

Charge for 7.62 × 53 mm sports rifle cartridge, including spherical powder, placed in a sleeve with an igniter capsule, characterized in that the charge is made of spherical dibasic powder with a bulk density of more than 1.0 kg / dm ³ , phlegmatized from the surface 3.5-5.0 wt.% Oligoester acrylate MGF-9 and 3.5-5.0 wt.% Centralite I in relation to the mass of gunpowder containing nitrocellulose with a nitric oxide content of 213-214 ml NO / g, nitroglycerin 19.0-21.0 wt.%, Diphenylamine 0.3-0.5 wt.%, Moisture 0.2-0.4 wt.%, Ethyl acetate 0.01-0.1 wt.%, Coated with a surface and graphite 0.1-0.3 wt.% in the following ratio of fractions, wt.%: (1.25-0.7) mm - not less than 80, more than 1.25 and less than 0.7 mm - not more than 20 .

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