Part One Cartridge Components


The cartridge case is the primary component with which we have to deal in reloading ammunition and its condition after firing, as well as its care, are of importance to the safety and accuracy of our reloaded ammunition. Early attempts to make brcrch loading arms were largely unsuccessful up to the time the cartridge case was invented, for despite attempts to seal the breech with carefully fined parts, gas would escape from there in close proximity to the shooter's face, a condition conducive neither to comfort, safety, good shooting or good ballistics. The brass cartridge case solved this difficulty because the thin walls of the case, pressed firmly against the chamber walls by the expanding gases, made a perfect "obturator" or gas seal and effectually prevented any escape of gas to the rear. THE CARTRIDGE CASE SHOULD ALWAYS BE THOUGHT OF AS A PART OF THE ARM IT IS FIRED IN and not merely as a convenient container for transporting charges and loading them into the gun.

For a better understanding of this function and the development of this important component, let us briefly look into its history. One of the first breech loaders that was considered as reasonably successful was the Sharps. This arm has a vertical sliding breech block which fits closely against the rear facc of the barrel. It used a linen cartridge 2 containing the bullet and powder, but was fired by a percussion cap. The cartridge, when inserted in the chamber, projected enough so that the sharp edge of the breech block sheared off the rear of the linen envelope in closing, leaving the powder exposed to the flash of the cap. When the arm was fired there was more or less cscapage of gas to the rear, causing erosion of the metal surfaces and consequently a continual increase in the escape of gas.

Another early breech loader was the German Dreyse or "needle gun" used by the German Army in the Franco-Prussian War. This was a single shot, bolt action rifle using a fabric cartridge which was peculiar in that the primer was placed at the base of the bullet and was fired by a long, sharp needle that penetrated the powder charge. There was a considerable cscapage of gas through the bolt of this rifle. The French pickcd the idea up and improved upon it in their Chasscpot' rifle by incorporating a rubber gasket or washer in the bolt which expanded and formed a gas seal under the pressure of the powder gasscs, however the sulphur in the powder quickly hardened the rubber and made it ineffective.

Other noteworthy advances were the Boxer cartridge used in the British Snider rifle and the French Lefaucheux or "pin fire" cartridge. The former employed a rimmed case of more or less conventional form, having a body of coiled

The Lefaucbeu Cartridge, brass and a separate head of cast iron. The latter was designed like the sketch shown herein, having a self-contained firing pin that projected from the side of the base. Arms using this cartridge had a notch in the breech of the chamber to accommodate this pin, which was struck by the hammer and driven against the internal primer. The Lc- 3 Eaucheux cartridge was not particularly convenient to handle, transport or load and was dangerous if dropped.

The first one piece, drawn brass cartridges cases of the type with which we arc familiar were made of thin brass with the heads or rims bent or folded, much as our present rim-fire cartridges are made today. The brass was so thin that it was usually nccessary to employ a reinforcing band of brass inside the case, near the head, to support the strain

The original folded head case. 5

at this point. These were the original and true ,4folded head'* cases, but they could not be resized as the heads were too thin to stand driving out of a resizing die. This type of case has not been manufactured for many years and is not likely to be encountered now, except in obsolete cartridges of considerable age. Becausc these early cartridges were expensive, reloading was universal and most arms manufacturers supplied reloading tools for the users o£ their arms. Winchester, Remington and Smith Ac Wesson made their own, but Colt seems to have catalogued and supplied Ideal reloading tools to the users of their revolvers.

Naturally, the reloaders of the time were not satisfied with the thin, folded head type of cartridge case. The corrosion causcd by the use of black powder quickly weakened the brass, the expansion of eases due to firing was severe and they could not be resized. There was, therefore, a universal demand for a stronger case that would overcome these objections, so the solid head type of case was developed. This type was drawn out in the form of a cup, the walls of which increased in thickness towards the bottom, this latter being the thickest part. This bottom, or base, was later mashed or cold forged to form the rim, 4 while the primer pocket was bent or forced into the metal of the head, just as it was in the older folded head ease. The difference in the primer pockets of these two types of case was practically in the thickness of the metal, and in both types the formation of the primer pocket created a raised hump on the inside of the head of the case. Strangely enough, this cartridge case that was once hailed with joy by reloaders; this case that came in boxes boldly labeled "solid head," and with directions that cxtoled their virtues for reloading purposes, are today known as "folded head"

cases. The term "folded head" is not a correct one to apply

The original soUd head case—today known as the folded head.

to them, as a comparison of the cross sections of the different types of cases shown here will make it clear that their heads are not really folded at all. Nevertheless, the term is in common use and throughout this book the term "folded head" will be used in referring to this type of cartridge case, unless explained to the contrary.

But this new case had its limitations also. It was satisfactory with black powder loads, which rarely developed pressures of more than 30,000 lbs. per square inch- When smokeless powder came into use and chambcr pressures were increased up to 45,000 and even 50,000 lbs. per square inch, thicker and stronger case heads were necessary. During this period of transition the Ideal Everlasting case was brought out.

The Ideal Everlasting case was a drawn brass case with thick side walls, much thicker than commercial cases of the time, and with solid heads, as we employ the term today. That is, the rim and head of the case were one solid mass of metal, with the primer pocket forged or mashed into the brass, without indenting the interior of the case at all. Incidentally, these cases often had the primer pockets carefully reamed to size. The walls of Everlasting cases were too thick to permit crimping and they were only suitable for use in single shot rifles. They were expensive, but were practically "everlasting" when properly cleaned and cared for after firing. The illustration here shown is of

The Ideal Everlasting case. Modern solid head cases of today are made on this principle.

a .40/90 Ballard Everlasting ease, it will serve to give an idea of the heavy structure of Everlasting cases, which were only made for straight or straight taper chambers. The thickness of these cases depended upon chamber and bullet diameters.

The use of solid head cases became general for all smokeless rifle cartridges developing high pressures. In recent years, with the development of the so-called high speed revolver cartridges, the use of solid h«ad cases tven extended to some revolver calibers and the folded head type is fast disappearing.

In this rather sketchy description of the development of the cartridge case, there has been no purpose other than to show that this component has been improved and strengthened from time to time with the object of holding in the powder ga«es, which is the primary junction of a curiridgc case. The chambcr and bolt or brecch block of an arm are insufficient to do tin's and these parts only act as supports for the case, which is in reality a part of the arm it is fired in and I repeat that it is important that the handloadcr always view the cartridge case in this light.

How Cartridge Cases Are Made. Cases are still 6 made of brass as this material can be easily obtained, it has the ncccssary strength if properly worked and it can be fabricated more cheaply than some other metals. Steel can and has been manufactured into cartridge cases but while steel is a much cheaper material than brass, it is far more expensive to fabricate and the high manufacturing cost much more than offsets any saving in the cost of the raw material. Incidentally, the use of steel cartridge cases would p_

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