I. Read the text and circle the information that is not mentioned in the text.

1) the purpose of ammunition

2) types of ammunition

3) storage of ammunition

4) naval ammunition

5) bullet design and manufacture

6) case design

7) cartridge assembly

8) raw material

9) supply ammunition in the field

10) modern ammunition

Ammunition is all material used for war. It covers anything that can be used in combat that includes bombs, missiles, warhead, and mines ( landmines, naval mines, and anti-personnel mines ). The purpose of ammunition is to project force against a selected target. Ammunition is the projectiles and propelling charges used in small arms, artillery, and other guns. Ammunition size is usually expressed in terms of caliber, which is the diameter of the projectile as measured in millimeters or inches. In general, projectiles less than 20 mm or 60 inch in diameter are classified as small-arm, and larger calibers are considered artillery. A complete round of ammunition consists of all the components necessary for one firing of the gun.

Modern ammunition includes artillery and mortars and aircraft-delivered bombs, smart bombs, rockets and other explosive-bearing projectiles. The design of the ammunition is determined by its aim; anti-personnel ammunition is often designed to break up inside the target, in order to maximize the damage done. Anti-personnel shells contain shrapnel and are designed to explode in mid-air, so its fragments will spread over a large area.

The components of ammunition may be divided into these categories:

• explosives and propellants
• projectiles of all kinds
• cartridges

Small arms ammunition, or cartridges, are used in a variety of firearms ranging from pistols to rifles and shotguns to heavier automatic weapons sometimes called machine guns. The term “ bullet” is commonly used to describe the cartridge, when in fact, it is the projectile. The correct terminology for the cartridge components are bullet, case, primer, and propellant or gunpowder. Each component is manufactured separately and then assembled into the cartridge. Bullets are made of a lead alloy, often containing tin and antimony. Some bullets have a thick jacket of copper over the outside for improved performance.

Cases are made of brass, steel, or aluminum. Brass is the most common. Shotgun shells are often made with a polypropylene plastic case attached to a metal base. Primers are made of a copper or brass alloy cup with a brass anvil and are filled with an impact-sensitive lead igniter. The metal parts of the primer are usually nickel-plated to resist corrosion.

Propellants can vary from black gunpowder to a more modern smokeless powder which contains nitrocellulose. Propellants are carefully formulated to ignite and create an expanding gas that accelerates the bullet down the barrel.

Bullets can be made by several different processes. Smaller 22 caliber bullets are usually lead and are pressed, or cold formed, into shape. A small piece of thick lead wire is cut to the correct length and formed into the bullet shape by a die set in an automatic press. Many handgun and rifle bullets used for competition shooting are cast using conventional casting methods. The molten lead is poured into the bullet mold cavity, cooled quickly, and then extracted from the mold. The point at which the lead enters the cavity is trimmed away as the bullet is extracted. Both cold-formed and cast bullets may be further improved by copper plating. The plating process electrically deposits a thin layer of copper on the outside of the bullet, protecting the lead from oxidation and providing a harder surface to engage the grooves or rifling in the barrel which give the bullet a spin to improve accuracy. To improve bullet performance and accuracy, the “jacketed” bullet was developed. This is a family of bullets that use a substantial brass or copper outer shell, usually filled with lead by casting or cold forming.

Specialized bullets are sometimes found in military applications. Armor-piercing bullets can be solid brass or copper jacketed steel core. These can penetrate engine blocks and aircraft frames, damaging mechanisms inside. Small arms ammunition cases are of brass alloy. Some use aluminum, steel, or plastic, but the brass case is most popular and easiest to manufacture.

The design of the case is determined by the firearm in which the ammunition is used. The typical brass case is formed from annealed sheet by drawing with a multiple punch and die set. The first stage of the multiple die set forms the metal, the second stretches the metal deeper, the third forms the rim, and so on. Each step stretches the metal slightly farther until the final stage produces an accurately formed case. Some handgun caliber cases are nickel plated for durability in reloading, corrosion resistance. Each case is stamped with information such as caliber, manufacturer, munitions codes, and year of manufacture.

The primer consists of two metal parts and a small amount of explosive compound. Primers come in different sizes depending on the firearm. Using a small pistol primer as an example, the cup is usually about 0.125 inch (0.32 cm) in diameter and 0.125 inch (0.32 cm) tall, and made of soft copper or brass. Inside is placed a small amount of the impact-sensitive explosive lead. When struck by the firing pin, the center of the cup collapses, squeezing the explosive between its inner surface and the anvil. The explosive ignites and shoots a flame through the flash hole, igniting the propellant to fire the cartridge.

This is how a typical center-fire metal cartridge is assembled:

• The cases are fed into a loading press which first sizes the case.
• The primer is then pressed into the case primer hole flush with the base. The primer must be flush or the cartridge will not feed properly in the weapon magazine, causing a “jam”.

• The case is “charged”, or filled with the correct amount of propellant. This step is important, for miscalculation or double charging could be disastrous.

• The bullet is firmly seated into the open end of the case. The bullet has a coating of lubricant to prevent corrosion and assist in the assembly process. The bullet is then crimped into the case to give the correct overall length of the cartridge. The crimp reduces the diameter of the open end of the case and captures the bullet tightly, sealing the assembly together so moisture cannot invade the powder.

The press used to assemble cartridges must feed each component accurately and in the correct sequence. Otherwise, cases could be unprimed, powder left out, or bullets seated incorrectly. Any of these could result in a misfire or loss of accuracy. After assembly, the finished cartridges are packaged, usually 50 to a box, and prepared for shipment to the shooter.

Most manufacturers shoot thousands of their own cartridges as part of their quality control programs and processes. The accuracy, pressure, reliability, velocity, and consistency are all recorded. Each production run of a particular cartridge is given a “lot code”. This number, printed on the ammunition box, allows ammunition to be inventoried and traced. Should a particular lot show problems in the field, that group can be recalled and replaced.

II. Match the words with the Russian equivalents:

1) pistol a) патрон

2) hand gun, machine gun b) пистолет

3) rifle n., v. c) подрезать

4) shooting d) пулемет

Case e) извлекать

Mold f) винтовка, нарезать канал ствола

Lead g) прочность, долговечность

Extract h) свинец

Trim away i) стрельба

Accuracy j) точность

Shell k) дробовик

Shotgun l) гильза

Firearm, weapon m) отливать, формовать

Durability n) огнестрельное оружие

Primer o) снаряд

Cartridge р) запал

III. Look at the groups of words below. Which is the odd one out in each group?

A. shell b. cartridge c. round d. bullet

A. handgun b. firearm c. shotgun d. rifle

A. break up b. damage c. explode d. divide

A. personnel b. antimony c. brass d. polypropylene

A. annealed b. determined c. stretched d. squeezed

A. bullet b. case c. primer d. cartridge

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