Magazine (firearms)

A staggered-column 9 x 19 mm pistol magazine.

A magazine is an ammunition storage and feeding device within or attached to a repeating firearm. Magazines may be integral to the firearm (fixed) or removable (detachable). The magazine functions by moving the cartridges stored in the magazine into a position where they may be loaded into the chamber by the action of the firearm. The detachable magazine is often referred to as a clip; the correctness of this usage has been the subject of debate for most of a century.

Magazines come in many shapes and sizes, from bolt action express rifles that hold only a few rounds to machine guns that hold hundreds of rounds. Since the magazine is an essential part of most repeating firearms, they are often subject to regulation by gun control laws seeking to limit the number of cartridges they hold.

History of the magazine

M1 Garand rifles 8-round en-bloc clip, M14 rifles 20-round magazine, 20- and 30-round M16/AR15 type STANAG Magazines.

The earliest firearms were loaded with loose powder and a lead ball, and to fire more than a single shot without reloading required multiple barrels, such as is still found in double barreled shotguns, or multiple chambers, such as in revolvers. Both of these add bulk and weight over a single barrel and chamber, however, and many attempts were made to get multiple shots from a single loading of a single barrel through the use of superposed loads. Breech loading designs such as the needle gun, and paper cartridges sped the loading process, but successful repeating mechanisms did not appear until self contained cartridges were developed.

Early lever actions

The first successful repeater to appear was the Volcanic Rifle, which used a hollow bullet with the base filled with powder and primer (an early form of caseless ammunition) fed into the chamber from a spring-loaded tube called a magazine, named after a building or room used to store ammunition. While the anemic power of the Rocket Ball ammunition used in the Volcanic doomed it to limited popularity, the basic design of the tubular magazine and lever action survive to this day.

The first magazine fed firearm to achieve widespread success was the Spencer rifle, which saw service in the American Civil War. The Spencer used a tubular magazine located in the butt of the gun, rather than under the barrel, and used new rimfire metallic cartridges. The Spencer was successful, but the rimfire ammunition did occasionally ignite in the magazine tube, which would destroy the rifle and potentially injure the user. The lever action Henry and Winchester rifles, evolved from the earlier Volcanic, saw service with a number of militaries, such as Turkey, while Switzerland and Italy adopted similar designs.

Early bolt actions

Lever action rifles, however, were not the future for military use. Beginning in the 1880s, the new bolt action rifle began to gain favor with militaries, and these were often equipped with tubular magazines. The Mauser Model 1871, originally a single shot action, added a tubular magazine in its 1884 update, and the Jarmann M1884, adopted the same year, also used one. The Lebel Model 1886 rifle, the first rifle and cartridge to be designed for use with smokeless powder, used an 8mm wadcutter-shaped bullet, loaded from a tubular magazine. This later became a problem as the Lebel's ammunition was updated to use a more aerodynamic pointed bullet, as modifications had to be made to the centerfire case to prevent the point of a bullet from igniting the round in front of it in the magazine. In 1890 the French adopted a new rifle, firing the same 8mm cartridge, that fed from en-bloc clips; the clips were required for feeding from the internal magazine, and empty clips were pushed from the bottom of the action by the insertion of a loaded clip from the top.

The bolt action Krag-Jørgensen rifle, invented in 1886, used a unique rotary magazine that was built into the receiver. It held the rounds side-by-side, rather than back-to-front. Like most tubular magazines, it was loaded through a loading gate, this one located on the side of the receiver. While reliable, the Krag-Jørgensen's magazine was expensive to produce, and was adopted by only a few countries, including it's home of Norway, Denmark, and the United States.

Development of the box magazine

The Russian Mosin-Nagant, adopted in 1891, was the first major military rifle to use a box magazine, stacking rounds vertically. Mauser was also developing box magazine fed variants of its Model 1871 during this time, with models from 1889 through 1893 in various calibers were adopted by various militaries at this time. An advantage of these design is that the internal magazine could be loaded quickly loaded with a new device called a stripper clip, which held five rounds clipped together. The bolt was opened, and the clip (called a charger by the British) slipped into a bracket, where the cartridges could be pushed out of the clip and into the magazine with one motion. The Krag-Jørgensen could be also be loaded from a clip of ammunition, but to do so required manipulation of the magazine loading gate. In various lengths and configurations, the basic Mosin-Nagant action remained the standard infantry rifle of Russia, and later the Soviet Union, though World War II.

The Lee-Metford rifle, developed in 1888, used an eight or ten round detachable box magazine, as did the Borchardt C-93, an early semiautomatic pistol developed in 1893. While the Borchardt set the standard for semiautomatic pistols to use detachable box magazines, the Lee-Metford, designed for the first generation, black powder version of the .303 British cartridge, was quickly rendered obsolete in 1895 by the smokeless powder .303 rounds, and the fixed magazine Lee-Enfield rifle that was designed for them.

The clip loaded, magazine fed bolt action rifle quickly became a standard around the world, with the adoption of the M1895 Lee Navy and the Gewehr 1888. By the turn of the 20th century, with the appearance of models like the Gewehr 98 and M1903 Springfield rifle, the pattern was set for the standard infantry rifles of World War I and much of World War II.

World War II and later

One of the last new clip-fed, fixed magazine rifles widely adopted (one that wasn't just a modification of an earlier rifle) was the M1 Garand rifle. The first semi-automatic rifle that was issued in large numbers to the infantry, the Garand was fed by a special eight round en-bloc clip. The clip itself was inserted into the rifle's magazine during loading, where it was locked in place. The rounds were fed directly from the clip, with a spring-loaded follower in the rifle pushing the rounds up into feeding position. When empty, the bolt would lock open, and a spring would automatically eject the empty clip, leaving the rifle ready to be reloaded. The system had its problems, however; it was impractical to top off the magazine, or load the action with anything less than a full clip, and the rifle could only be used to fire single shots without a clip present. The M14 rifle, which was based on incremental changes to the Garand action, switched to a detachable box magazine.

The Soviet SKS carbine, which entered service in 1945, was something of a stopgap between the semi-automatic service rifles being developed in the period leading up to World War II, and the new assault rifle developed by the Germans. The SKS used a fixed magazine, holding ten rounds and fed by a conventional stripper clip. It was a modification of the earlier AVS-36 rifle, shortened and chambered for the new reduced power 7.62 x 39 mm cartridge. It was rendered obsolete for military use almost immediately by the 1947 introduction of the AK-47 assault rifle, though it remained in service for many years in Soviet bloc nations alongside the AK-47. The detachable magazine quickly came to dominate post-war military rifle designs.

What to call it?

With the increased use of semi-automatic and automatic firearms, the detachable box magazine become increasingly common. There was a period of time when the term "clip" was used for these, such as in the English translations of the Chauchat light machine gun manuals and the early testing by the United States for a semiautomatic pistol. Soon after the adoption of the M1911 pistol, the term "magazine" was settled on by the military and firearms experts, though the term "clip" is often used in its place (though only for detachable magazines, never fixed). The defining difference between clips and magazines is the presence of a feed mechanism in a magazine, typically a spring loaded follower, which a clip lacks. Most experts strongly reject the use of the term "clip" to refer to detachable magazines.

Magazine types

Magazines come in many shapes and sizes, with the most common type in modern firearms being the detachable "box" type. Some magazine types are strongly associated with certain firearm times, such as the fixed "tubular" magazine found on most lever-action rifles and pump action shotguns. A firearm using detachable magazines may accept a variety of types of magazine, such as the Thompson submachine gun, which would accept box or drum magazines. Some types of firearm, such as the M-249 and other squad automatic weapons, can feed from both magazines and belts.

Box

The most popular type of magazine in modern rifles and handguns, a box magazine stores cartridges in a column, either one above the other or staggered zigzag fashion. This zigzag stack is often identified by the misnomer double-column when in fact, it is a single, staggered column. As the firearm cycles, cartridges are moved to the top of the magazine via spring tension to either a single feed position or side-by-side feed positions. Box magazines may be integral to the firearm or removable.

• An internal box or fixed magazine (also known as a blind box magazine when lacking a floorplate) is built into the firearm and is not easily removable. This type of magazine is found most often on bolt-action rifles. An internal box magazine is usually charged through the action, one round at a time. Military rifles often use stripper clips or chargers permitting multiple rounds, commonly 5 or 10 at a time, to be loaded at once. Some internal box magazines use en-bloc clips that are loaded into the magazine with the ammunition and that are ejected from the firearm when empty.

Detachable box magazine for a SG 550.

• A detachable box magazine is a self-contained mechanism capable of being loaded or unloaded while detached from the host firearm. They are attached via a slot in the firearm receiver usually below the action but occasionally to the side (FG42, Johnson LMG) or on top (Bren gun, FN P90). When the magazine is empty, it can be detached from the firearm and replaced by another full magazine. This significantly speeds the process of reloading, allowing the operator quick access to ammunition. This type of magazine may be straight or curved, the curve being necessary if the rifle uses rimmed ammunition or ammunition with a tapered case. Box magazines are often affixed to each other with clips, tape, straps, or otherwise, for quicker access.

There are, however, exceptions to these rules. The Lee-Enfield and Tokarev SVT-40 rifles had a detachable box magazine only to facilitate cleaning. The Lee-Enfield magazine did open, permitting rapid unloading of the magazine without having to operate the bolt-action repeatedly to unload the magazine. Others, like the Breda Modello 30, had a fixed protruding magazine that resembled a conventional detachable box but was non-detachable.

Tubular

Many of the first repeating rifles, particularly lever-action and slide-action types, used a single or multiple tubular magazines that store cartridges end-to-end inside of a spring-loaded tube typically running parallel to the barrel or in the buttstock. This type of magazine is usually fixed to the firearm, meaning that it is not removed in use. Tubular magazines can still be found today, commonly in shotguns, rimfire rifles, or firearms designed to use round-nose, flat-nose, or otherwise soft-pointed bullets. The tubular magazine was made obsolete for most military purposes with the introduction of pointed "Spitzer" bullets that risk igniting cartridges stored in the magazine as the pointed bullet impacts the primer of the centerfire cartridge ahead of it during recoil.

Rotary

The rotary or spool magazine consists of a star-shaped rotor, or sprocket, actuated by a torsion spring. The magazine may be fixed or detachable. Cartridges fit between the teeth of the sprocket, which is mounted on a spindle parallel to the bore axis, with a torsion spring providing the pressure necessary to rotate the rounds into the feeding position. Rotary magazines are usually of low capacity of ten rounds or less, depending on the cartridge used. The rotary magazine was first used in the Mannlicher-Schönauer rifles and is still used in a few modern firearm designs, most notably the Ruger 10/22 and the Steyr SSG 69.

Drum

Main article: Drum magazine

Today, drum magazines are used primarily for light machine guns. In one type, a moving partition within a cylindrical chamber forces loose rounds into an exit slot, with the cartridges being stored parallel to the axis of rotation. After loading of the magazine, a wound spring or other mechanical force the partition against the rounds. In other designs, notably the Beta C-Mag, a single staggered column is pushed by a follower through a curved path either from a single or dual drums.

Cylindrical designs such as rotary and drum magazines allow for larger capacity than box magazines, without growing to excessive length. Drum magazines sacrifice reliability, though, being more complicated. Many drum-fed firearms can also load from conventional boxes, such as the Russian RPK light machine gun and the American Thompson submachine gun.

Pan

Often referred to as a drum magazine, the pan magazine differs from other drum magazines in that the cartridges are stored perpendicular to the axis of rotation, rather than parallel, and are usually mounted on top of the firearm. This type is used on the American-180 submachine gun and the Degtyarev light machine gun.

Helical

Helical magazines extend the drum magazine design so that rounds follow a spiral path, allowing for a very large ammunition capacity in a compact package but require a complex mechanism and increasing likelihood of unreliability. Examples are the Calico 960 and Bizon submachine guns.

High capacity magazines

The term high capacity magazine is a term used to describe magazines that exceed a certain "normal" capacity, whose definition is dependent upon context. In many jurisdictions, magazine capacity of certain firearms is legally restricted, such as under the United States' Federal Assault Weapons Ban, which defined a magazine capable of holding more than ten rounds of ammunition as a high capacity ammunition feeding device. Currently, in the United States, six states limit magazine capacities.

Many pistol and rifle magazines classified by such laws as "high capacity" are in fact the factory standard magazines originally designed for use with their respective firearms. Reduced capacity magazines, generally holding ten rounds, were created subsequently in response to enactment of the bans.

External links

• Difference Between a Magazine and a Clip video