Overall length

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The overall length (OAL) of an ammunition cartridge is a measurement from the base of the brass shell casing to the tip of the bullet, seated into the brass casing. Cartridge overall length, or "COL", is important to safe functioning of reloads in firearms. [1]

Handloaded cartridges and commercially available cartridges for firearms are normally created with a maximum length standardized by the Sporting Arms and Ammunition Manufacturers' Institute (SAAMI). A cartridge's overall length may be shorter than the maximum standard, equal to the standard, or sometimes even longer.

The maximum overall length is dictated by the need to fit into a box magazine of standard manufacture. For example, the .223 Remington cartridge, when loaded for use in the AR-15 rifle (or the military's M16 rifle), has to fit into the removable box magazine for that rifle. This dictates that the cartridge's maximum overall length be no greater than 2.260". However, for competition purposes during off-hand and slow fire prone match stages, the .223 Remington is loaded one cartridge at a time into the rifle's receiver. This allows for the cartridge to be longer than the standardized 2.260" SAAMI maximum overall length. These cartridges can be safely loaded to a length that has the ogive portion of the bullet just touching the rifle's lands. Many competitive shooters will make these cartridges 0.005" less than the truly maximum allowable overall length, for the sake of safety. [2]

It is desirable for these single-loaded cartridges to have as little bullet jump as possible before the bullet's ogive begins to be engraved by the rifle's lands. This minimized bullet jump increases the accuracy of the rifle, all else being equal. This practice of long-loading a cartridge must be adjusted for each individual rifle, since there are variations from rifle to rifle as to how far down the barrel the rifling begins. [2]

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Handloading or reloading is the process of making firearm cartridges or shells by manually assembling the individual components, rather than purchasing mass-assembled, factory-loaded ammunition.

Cartridge (firearms) type of ammunition packaging that includes a bullet or shot, a propellant substance, and a primer within a metallic, paper, or plastic case

A cartridge or a round is a type of pre-assembled firearm ammunition packaging a projectile, a propellant substance and an ignition device (primer) within a metallic, paper or plastic case that is precisely made to fit within the barrel chamber of a breechloading gun, for the practical purpose of convenient transportation and handling during shooting. Although in popular usage the term "bullet" is often used to refer to a complete cartridge, it is correctly used only to refer to the projectile.

.223 Remington Firearms cartridge

The .223 Remington is a rifle cartridge, developed in 1957 as a commercial hunting bullet for small mid-western varmint. Used as a test round for the ArmaLite's newer combat rifle in 1964, the ArmaLite AR-15 was adopted by the United States Army as the M16 rifle, The military version of the cartridge uses a 55-gr full metal jacket bullet and was designated M193. In 1980, the .223 Remington was transformed into a new cartridge, a 62-gr full metal jacket bullet with a 7-gr steel core for better penetration and designated 5.56×45mm NATO.

.308 Winchester Rimless, centerfire, bottlenecked rifle cartridge

The .308 Winchester is a smokeless powder rimless bottlenecked rifle cartridge.

Wildcat cartridge Custom cartridge for firearms

A wildcat cartridge, often shortened to wildcat, is a custom cartridge for which ammunition and/or firearms are not mass-produced. These cartridges are often created in order to optimize a certain performance characteristic of an existing commercial cartridge.

6.5×55mm Swedish Swedish military rifle cartridge

The 6.5×55mm Swedish is a first-generation smokeless powder rimless bottlenecked rifle cartridge. It was introduced in the 1890s, and is still one of the most common cartridges in modern rifles built for the Scandinavian market today. The cartridge was developed in a joint Norwegian and Swedish effort starting in 1891 for use in the new service rifles then under consideration by the United Kingdoms of Sweden and Norway. In 1893, the cartridge was standardized and adopted under the name 6.5×55 mm to facilitate logistical cooperation between Norway and Sweden. The two nations had independent armies and consequently the normal procedure at the time was for their respective governments to use the same ammunition and then purchase small arms of their choice. Norway adopted the Krag–Jørgensen M/1894 rifle, while Sweden adopted the Mauser m/1896 rifle design that was based on a Mauser service rifle designed around the 7×57mm Mauser cartridge.

6mm PPC cartridge

The 6mm PPC, or 6 PPC as it is more often called, is a centerfire rifle cartridge used almost exclusively for benchrest shooting. At distances out to 300 meters, it is one of the most accurate cartridges available. This cartridge's accuracy is produced by a combination of its stout posture, being only 31 mm (1.22 in) long, and aggressive shoulder angle of 30 degrees compared to a 30-06's 17 degrees. Today it is commonly used for railgun shooting matches and has been since the 1980s.

.300 Winchester Magnum Belted, bottlenecked magnum rifle cartridge

The .300 Winchester Magnum (7.62×67mmB) is a belted, bottlenecked magnum rifle cartridge that was introduced by Winchester Repeating Arms Company in 1963. The .300 Winchester Magnum is a magnum cartridge designed to fit in a standard rifle action. It is based on the .375 H&H Magnum, which has been blown out, shortened, and necked down to accept a .30 caliber (7.62 mm) bullet.

The .222 Remington Magnum was a short-lived commercially produced cartridge derived from the .222 Remington. Originally developed for a US military prototype Armalite AR-15 rifle in 1958, the cartridge was not adopted by the military, but was introduced commercially in sporting rifles.

.17 Hornet cartridge

The .17 Hornet is a .17 caliber centerfire rifle cartridge originally offered as a "wildcat cartridge" made by P.O. Ackley in the early 1950s. He created this non-factory (wildcat) offering by simply necking-down the .22 Hornet to .17 caliber and fire-forming the resized cases in his new chamber design. The result was a small quiet cartridge capable of high velocity. Ackley mentions it as one of the most balanced of the .17 cartridges of his time; likely, this is still true.

The .260 Remington cartridge was introduced by Remington in 1997. Many wildcat cartridges based on the .308 Winchester case had existed for years before Remington standardized this round.

.416 Remington Magnum cartridge

The .416 Remington Magnum is a .416 caliber (10.57 mm) cartridge of belted bottlenecked design. The cartridge was intended as a dangerous game hunting cartridge and released to the public in 1989. The cartridge uses the case of the 8 mm Remington Magnum as a parent cartridge. When the cartridge was released in 1988, author Frank C. Barnes considered the .416 Remington Magnum to be the "most outstanding factory cartridge introduced in decades".

.450 Bushmaster Rifle cartridge

The .450 Bushmaster is a rifle cartridge developed by Tim LeGendre of LeMag Firearms, and licensed to Bushmaster Firearms International. The .450 Bushmaster is designed to be used in the standard M16s and AR-15s, using modified magazines and upper receiver assemblies.

P.O. Ackley Gunsmith, author and columnist

Parker Otto Ackley was an American gunsmith, barrel maker, author, columnist, and wildcat cartridge developer. The Ackley Improved family of wildcat cartridges are designed to be easily made by rechambering existing firearms, and fireforming the ammunition to decrease body taper and increase shoulder angle, resulting in a higher case capacity. Ackley improved not only standard cartridges, but also other popular wildcats, and was the first to create a .17 caliber (4.5 mm) centerfire cartridge.

6.5mm Creedmoor Centerfire rifle cartridge

The 6.5mm Creedmoor, designated 6.5 Creedmoor by SAAMI, 6.5 Creedmoor by the C.I.P. or 6.5 CM or 6.5 CRDMR for short, is a centerfire rifle cartridge developed for Creedmoor Sports and introduced by Hornady in 2007. It is a modification of the 6.5 Carcano and the .30 TC, based on the .308 Winchester.

The 6×45mm is a rimless, bottlenecked cartridge based on the .223 Remington or 5.56 NATO cartridge necked up to .243 (6mm). The cartridge is also known as the 6mm-223 Remington or 6mm/223.

9×23mm Winchester Rimless pistol cartridge

The 9×23mm Winchester is a pistol cartridge developed as a joint venture by Winchester Ammunition and Colt's Manufacturing Company. The 9×23mm Winchester has a convoluted development history, but was commercially introduced by Winchester in 1996. Marketed primarily to competition shooters as a replacement for .38 Super for International Practical Shooting Confederation, United States Practical Shooting Association and International Defensive Pistol Association competition, the cartridge failed to find significant market success despite a high-profile introduction.

.30-06 Springfield wildcat cartridges cartridge

.30-06 Springfield wildcat cartridges are cartridges developed from a 30-06 Springfield "parent cartridge" through narrowing or widening the cartridge neck to fit a smaller or larger bullet in an attempt to improve performance in specific areas. Such wildcat cartridges are not standardized with recognized small arms standardization bodies like the SAAMI and the CIP.

The .277 Wolverine (6.8×39mm) is a wildcat cartridge. It is a multi-purpose mid-power cartridge with increased ballistic performance over the AR-15's traditional .223 Remington cartridge requiring only a new barrel to upgrade/convert any 5.56-based firearm to .277 Wolverine.

Nosler proprietary cartridges

Nosler produces various high performance hollow point and soft point hunting bullets.

References

  1. Barnes, Frank C.; Holt Bodinson; Layne Simpson (2009). Cartridges of the World: A Complete and Illustrated Reference for Over 1500 Cartridges (12 ed.). Gun Digest Books. p. 157. ISBN   978-0-89689-936-0.
  2. 1 2 James, Rodney (2011). The ABCs of Reloading: The Definitive Guide for Novice to Expert (9 ed.). Krause Publications. p. 127. ISBN   978-1-4402-1396-0.