History of Ammunition

The self-contained metallic cartridge is a relatively recent development in historical terms. Gunpowder has been in use as a firearms propellant for about 670 years, but the metallic cartridge is only about 160 years old. The modern self-contained metallic cartridge was perfected about 122 years ago and high-velocity types with smokeless powders were developed about 102 years ago.23

Prior to the introduction of a self-contained cartridge, firearms were muzzle-loaded by pouring a measured amount of gunpowder down the barrel followed by the bullet and then compacting the gunpowder/bullet combination by the use of a plunger and some sort of wad. Ignition of the gunpowder was accomplished separately. Obviously, this system suffered several major disadvantages. Faster reloading in order to achieve greater firepower was desirable, the means of ignition was susceptible to weather conditions, and it was necessary to carry items of equipment ancillary to the firearm, that is, gunpowder, ignition powder (finely powdered gunpowder), bullets, wads, and ramming rod. Because of the long loading time, the advantages of a self-contained ammunition package were evident early in the history of firearms and many attempts were made to produce such a package.

One of the earliest attempts to decrease loading time was a breech-loading matchlock firearm with the rear end of the barrel counter bored to give a larger diameter than the rest of the bore. A removable iron chamber complete with its own flash pan and loaded with gunpowder and bullet was inserted. Extra loaded insert chambers could be carried.24

A paper cartridge was developed about 1550 and consisted of gunpowder and bullet wrapped in a cylinder-shaped paper package or a small paper bag of gunpowder attached by thread to the bullet. In use the bottom of the paper cartridge was torn open (usually with the firer's teeth), and the gunpowder and bullet poured down the barrel from the muzzle end after placing a small amount of gunpowder in the flash pan. The paper was sometimes rammed down the barrel and used as a wad to prevent the bullet dropping out of the barrel.

Various designs of the paper cartridge were in general use by the middle of the seventeenth century and paper was used for cartridge manufacture for about 300 years.

Whenever the complete cartridge, including paper, was loaded into the firearm, the paper cartridge case burned when the charge was fired. However, smoldering pieces of paper could remain in the barrel and on reloading an explosion could occur. This led to the introduction of a completely combustible paper cartridge, with the paper nitrated prior to assembly. Nitrated animal intestines were also used in cartridges during this period. The paper cartridges caused problems in damp weather and the cartridges had to be carried in waterproof containers. Several attempts were made to waterproof paper cartridges using varnish but this did not achieve widespread acceptance.

The earliest example of a fully self-contained cartridge was produced by Swiss engineer Jean Samuel Pauly in 1808. This cartridge was loaded directly into the breech of a firearm, which was also developed by Pauly, and was fired by a needle piercing it.

An improved form of the cartridge was patented by Pauly in 1812. It consisted of a paper body rolled around the front portion of a rimmed brass base piece, the base of which had a central recess to contain the primer powder, which was sealed with a small piece of gummed paper to retain it in position and protect it from moisture.25

This was one of the most important developments in firearm history and is the earliest example of a fully self-contained centerfired cartridge. However, the system did not gain widespread acceptance as it applied only to firearms of Pauly's design. It did establish the principle of a completely self-contained cartridge, that is, a cartridge with its own means of ignition as an integral part. Figure 5.1 gives a cross-sectional view of the Pauly cartridge.

The next cartridge with an integral primer was the needle-gun cartridge developed by a Prussian, Johann Nikolas Dreyse, in 1831. In its original form it was made with either a paper or linen envelope and in its later form it was made entirely of paper. It had a flat base and was tied shut above the bullet which was contained in a sabot. There was a recess in the base of the

Closure

Bullet

Primer powder

1846 Caseless Cartridge

Closure

Bullet

■ Paper cartridge case

■ Paper cartridge case

- Black powder propellant

- Rimmed brass base

Figure 5.1 Pauly cartridge.

Jean Samuel Pauly Cartridge

Bullet

Black powder propellant

Mercury fulminate paste

Paper cartridge case

Bullet

Black powder propellant

Mercury fulminate paste

Paper cartridge case

Figure 5.2 Dreyse cartridge.

sabot that contained a mercury fulminate paste. Ignition of the cartridge was accomplished by a long spring-operated needle which had to penetrate the full length of the gunpowder charge to reach the mercury fulminate. Figure 5.2 gives a cross-sectional view of the Dreyse cartridge.

Further development of the needle-gun concept led to a pasteboard cartridge case with the primer in the base portion in the form of a shallow metal foil cup containing a flanged percussion cap with its open end facing the base of the cartridge. A small hole was made through the center of the base and metal foil cup, and the cap was ignited by the penetration of a short firing needle.

An innovation not involving a conventional cartridge case was introduced by Joseph Rock Cooper in 1840. This was a bullet with a charge of gunpowder placed in a cavity at the base of the bullet. Ignition was by means of an external percussion source. Development of this concept by other workers culminated in a cone-shaped bullet with a charge of gunpowder in a base cavity which was closed by a cork plug and fitted with a priming system.26

As there was nothing to prevent the rearward escape of gas and as the bullet itself had only about 1/15 its weight in gunpowder charge, the bullet lacked power. Misfires were common and the system was abandoned about 1856.

Until 1846 all attempts to develop a satisfactory fully self-contained cartridge shared a serious disadvantage. None of them effectively sealed the chamber at the time of discharge and consequently there was a rearward escape of gas resulting in a reduction in the efficiency of the system. This problem was solved by the introduction of the metallic cartridge case which momentarily expands during the discharge process and seals the chamber.

The first recorded examples of fully self-contained completely metallic cartridges were the pinfire cartridges of the early 1850s. These consisted of a thin copper cartridge case with a striker pin projecting radially from the base end (brass came into general use in the 1870s and replaced copper as the case

Cartridge case

Cartridge case

_L

¿aasasl

---

J&Sm P'if?

' "BM issSiisSis

Bullet

Propellant

' ■ '51.

1

Figure 5.3 Pinfire cartridge.

Figure 5.3 Pinfire cartridge.

material). The striker pin was aimed at the priming composition but positioned just clear of it. Figure 5.3 gives a cross-sectional view of the pinfire cartridge.

By effectively sealing the bore during discharge the pinfire cartridges made breech loading a much more practical proposition and these cartridges were manufactured until the late 1930s. A major disadvantage of this system was that because of the projecting pin the cartridge could be loaded in one position only.27

The next stage in cartridge evolution was the rimfire cartridge. The idea of a cartridge with a hollow rim to contain the priming composition was patented by French gunsmith Houllier in 1846 and developed by another French gunsmith, Flobert. The cartridge was originally produced with no gunpowder charge, the priming composition serving as both igniter and propellant.

In 1854 the American firm of Smith & Wesson developed the design by lengthening the case so that it could hold a charge of gunpowder. The rimfire system became very popular and was manufactured in a range of calibers. A major advantage of the rimfire cartridge was that it made possible the construction of firearms having a supply of cartridges housed in a magazine.

As firearms developed the trend was toward smaller and greater power and range and it was found that the thin metal base of the rimfire cartridge could not withstand the higher pressures involved. This was a disadvantage that could not be readily overcome and was one of the main reasons for the decline in popularity of the rimfire cartridge. Other disadvantages of the rimfire cartridge are unsuitability of design for modern firearm loading and ejection systems, the larger amount of priming composition that is required, and the manufacturing inconvenience of ensuring an even spread of priming composition around the rim.

Rimfire cartridges are still manufactured but only in 0.22" and 0.17" calibers and all other modern firearms ammunition is centerfire (central-fire).

Centerfire cartridges were produced by Pauly in 1808 but it was not until 1854 that the firm of Smith & Wesson perfected and patented both the center-fire and rimfire metallic cartridge case. Since this time cartridge development has consisted of many small improvements, some resulting from advances in engineering and metallurgy, some from improvements in firearms design, and some as a result of the development of modern smokeless propellants.

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

+1 0

Responses

  • brutus
    Who invented the self contained metallic firearm cartridge?
    16 days ago

Post a comment