Paper cartridge

A paper cartridge is one of various types of small arms ammunition used before the advent of the metallic cartridge. These cartridges consisted of a paper cylinder or cone containing the bullet, gunpowder, and, in some cases, a primer or a lubricating and anti-fouling agent. Combustible cartridges are paper cartridges that use paper treated with oxidizers to allow them to burn completely upon ignition.

History
Paper cartridges have been in use for nearly as long as hand-held firearms, with a number of sources dating their use back to the late 14th century. Historians note their use by soldiers of Christian I in 1586, while the Dresden museum has evidence dating their use to 1591, and Capo Bianco writes in 1597 that paper cartridges had long been in use by Neapolitan soldiers. Their use became widespread by the 17th century.

Cultural impact
Paper cartridges were often coated in beeswax, lard, or tallow, which served a number of purposes. It provided some degree of water resistance, it lubricated the paper-wrapped bullet as it was pushed down the bore, and it melted upon firing to mix with the powder residue and make the resulting fouling easier to remove. Since the standard procedure for loading a musket or rifled musket involved biting open the cartridge, this can cause problems for those with strict dietary restrictions. The Sepoy soldiers in the employ of the British in India, for example, were largely Hindu, who were forbidden to eat beef, or Muslim, who were forbidden to eat pork. Rumors of the use of lard and tallow in the lubrication of the cartridges they were using were part of the cause of the Indian Rebellion of 1857.

The 1944 Newbery Medal winning historical novel Johnny Tremain, set in Boston during the period leading up to the American Revolution, describes the making of paper cartridges.

Advantages of paper cartridges
The most common applications of paper cartridges were in muzzleloading firearms. While these may be loaded with loose powder and balls or bullets, a paper cartridge combines a pre-measured amount of powder with the ball in a sealed unit. This eliminated the operation of measuring the powder during loading. In the case where multiple projectiles were used, such as buck and ball loads, the cartridge also served to package up the projectiles, so they did not have to be measured or counted out. The paper also served as a patch in smoothbore firearms, which fired undersized balls sealed in the barrel by a paper or cloth patch.

The paper used in cartridges varied considerably. The instructions for making Enfield paper cartridges, published in 1859, which uses three pieces of paper of two different thicknesses, shows the complexity that could be involved. Some cartridges, such as those for percussion revolvers, used nitrated paper. Treated by soaking in a potassium nitrate solution and then drying, this made the paper far more flammable and ensured it burned completely upon firing.

Despite the complexity involved in their construction, paper cartridges were used through the time of the American Civil War, after which time they were displaced by modern metallic cartridges.

Construction and use of a paper cartridge
Paper cartridges varied in their construction based on the firearms for which they were used. There are a number of features which are not specific to the firearm, and so apply to any paper cartridge. For example, the cartridge must be sturdy enough to withstand the handling it can be expected to receive. This means either a sturdy paper must be used, or the cartridge must be reinforced for strength. The importance of paper cartridges can be seen by the existence of cartridge paper, a paper specially produced for the production of paper cartridges. In some cases the cartridges were produced directly from paper pulp, and formed into a seamless cylinder of the correct diameter.

Cartridges for smoothbore muskets
Smoothbore muskets were loaded with undersized lead balls, which were sealed using a patch of paper or cloth. A typical flintlock cartridge consisted of a paper tube, tied off in three places to form two compartments. The first compartment contained the projectile or projectiles, either a single round ball or a large round ball plus three buckshot in the case of a buck and ball load. The second compartment contained the charge of powder. To load the musket, the following steps were used: The paper, typically a thick, sturdy variety, serves to seal the powder gas behind the bullet, and keep the undersized bullet centered in the bore. As each shot leaves progressively more fouling in the barrel from the black powder, this makes each shot harder and harder to load. This can be helped by using a lubricant, which serves not only to help the ball slide down the barrel, but also serves to soften the fouling in the bore, so that it is pushed clear during loading.
 * Hold the musket level, place at half cock, and open the flash pan
 * Bite open a cartridge, pour a small quantity of powder into the pan, and close it
 * Hold the musket vertically, and pour the remaining powder down the barrel
 * Ram the ball and remaining paper down the barrel with the ramrod

Cartridges for percussion rifles
With the advent of the rifled barrel, it was no longer necessary to fire a spherical projectile—though the new elongated bullets were still called balls in the military. The Minié ball contained a number of innovations. The first was a deep cavity in the rear, which caused the base of the bullet to expand upon firing, allowing an undersized bullet to be used without a patch. The next was a number of grooves around the bullet, which were filled with lubricant. As noted before, this lubricant also serves to soften the powder fouling, which makes loading the fouled barrel much easier.

Because the bullet is closely matched in size to the bore, the paper around the bullet must be much thinner than in a smoothbore, to fit in the thin gap between bullet and bore. To meet this requirement, while still ensuring a rugged cartridge, the cartridges were made in multiple parts. The following describes the construction of a cartridge for a British Enfield musket, from the inside out: The bullet end of the cartridge was crimped shut, and the powder end was filled and folded closed. The bullet end of the completed cartridge was then dipped in a mixture of melted beeswax and tallow to lubricate the bullet.
 * A short tube of stiff paper, which provides the strength for the cartridge
 * A longer tube of thin paper, pushed inwards at one end, which serves to separate the powder from the bullet
 * A long tube of thin paper, which holds the bullet at one end, and the stiffened powder container at the other

To load the rifle, the powder end was opened up by unfolding or tearing, and the powder was poured into the rifle. The bullet end was then inserted up to the level of the thick paper tube, which was then torn off and discarded. The bullet was then seated with the ramrod, and the nipple primed with a percussion cap.

Nitrated cartridges for percussion revolvers
Percussion revolvers, while not truly muzzleloaders, are similar, as they load from the front of the cylinder. Typical paper cartridges for revolvers differ from the robust percussion rifle cartridges, in that the cartridge is inserted into the chamber whole, and rammed into place. Revolver cartridges were often combustible, and the bullet is typically exposed, with the paper cartridge glued, typically with sodium silicate, a high temperature glue that was widely available, as it was also used to preserve fresh eggs. Many examples were tapered, into a cone, being wider at the bullet than at the rear. Some commercially produced cartridges, such as those by Hayes of England, were also equipped with a small cloth tear tab at the front to assist in the removal of the protective outer layer prior to loading the cartridge.

The revolver paper cartridge lasted longer than it otherwise would have, and encompassed a wider range of forms, due to Rollin White's patent covering bored through cylinders on a revolver (adopted for a paper cartridge application). That patent was exclusively licensed by Smith & Wesson, giving them an effective monopoly on the American manufacture of effective cartridge revolvers until the patent expired. Prevented from converting to rimfire or centerfire cartridges, other manufacturers had to remain with percussion systems or develop proprietary front-loading cartridges.

Paper cartridges for breech loaders
The concept of a fully self-contained paper cartridge for a breech loader was patented in 1808, only a year after the invention of the percussion cap. One of the earliest breechloading firearms that was widely adopted was the Dreyse needle gun, patented in 1839, which was put to good use by the Prussian army. The needle gun used a complete cartridge, containing bullet, powder, and primer in a paper cartridge. The primer was located at the base of the bullet, and the firing pin, or needle, penetrated the back of the case, went through the powder, and struck the primer to ignite it.

The needle gun cartridge was far ahead of its time. Not only was it fully self-contained, and chambered in breechloading rifles, but it combined a number of very advanced features. First, the ammunition was effectively caseless, leaving little or no residue behind after firing. Second, it used forward ignition, where the powder charge is ignited at the front rather than the rear. This provides superior internal ballistics performance, even in modern ammunition, as shown by experiments in modern firearms by various experts, including Elmer Keith. The final feature is the use of a saboted subcaliber bullet. The acorn-shaped bullet used by the Prussians was carried in a Papier-mâché sabot which served not only to seal the bore, but also contain the primer.

The fragility of the breechloading needle gun was a primary reason that only a few militaries adopted the system; in the well trained Prussian army, this was handled by having each soldier carry several spare needles. This allowed the individual soldiers to repair their guns in the field.

Paper shotshells
Paper shotshells, consisting of a paper body with a brass base and rim, have continued to be made and used many years after their general replacement with plastic shotshells. The only areas where these are still used in fairly large numbers, though, are in extremely cold areas where plastic shells often split when fired at -40 degree C temperatures (-40F), and when handloading very low pressure rounds for extremely old shotguns. Paper shotshells consist of a coiled paper tube, placed in a brass base, with the web of the case made of compressed paper pulp. These cartridges are sturdy enough to be reloaded many times.