Bullpup

For the air to surface missile, see AGM-12 Bullpup

Steyr AUG is one of the most successful bullpup rifles

Bullpup is a firearm configuration in which the action (or mechanism) and magazine are located behind the trigger. This increases the barrel length relative to the overall weapon length, permitting shorter weapons for the same barrel length, saving weight and increasing maneuverability. It also allows for longer barrels on weapons of the same length, improving trajectory and accuracy.

The concept was first used in bolt action rifles such as the Thorneycroft carbine of 1901, and is known to have been applied to semi-automatic firearms no later than 1936, the year a bullpup pistol was patented by the Frenchman Henri Delacre. A 7.62 mm caliber experimental assault rifle was developed by Korovin in the Soviet Union in 1945. The EM2 was adopted by the United Kingdom in 1951 as the world's first (limited) service bullpup rifle; the nation had been considering the idea of a bullpup service rifle since 1944.

Worldwide use

Bullpups began to become mainstream military weapons in the late 1970s with the introduction of the Steyr AUG and FAMAS in Austria and France, respectively (the AUG later became the standard issue military rifle for several other countries). In 1985 Britain followed suit with the introduction of the SA80. Today, bullpups are common in modern military arsenals, and make up a large minority of military small arms. Recently Israel, Singapore, and China have all adopted locally-designed and produced bullpup rifles. The new F2000 may be adopted by a number of countries. New bullpup rifles actually outnumber new conventional-layout military rifles designed and introduced in the last several years. Some cite the increasingly urban nature of warfare as a reason for their increased popularity, their short length being useful in tight quarters.

Bullpups have also made an impact on the civilian market. Civilian versions of military bullpups are popular, and several dedicated sporting bullpup firearms have been produced, like the Bushmaster M17S and Walther G22. There are also aftermarket conversion kits for a variety of popular conventional rifles, like the AK-47 and Ruger 10/22, and even shotguns like the Mossberg 500.

Design issues

Bullpup weapons have been the subject of some debate and criticism. Mechanisms typically eject casings to the side. This means that a conventional bullpup design must be fired from only one side of the body, or the casings will hit the operator in the face. Some bullpups' designs allow the side of ejection to be switched during disassembly (e.g. the FAMAS and Tavor), while others, like the FN F2000 and A-91, eject forward. Still others, like the FN P90, eject downward, which usually (but not always) means the magazine is mounted on the top or sides of the weapon.

Other criticisms made of bullpup weapons are their heavy and sluggish trigger pull, caused by use of a flexible rod or similar system (fixed in the SAR-21 by using a stiff sliding plate instead), awkward magazine changes, poor balance, high sight position above the barrel (forcing the firer to expose more of his head when aiming over cover), reduced reach in bayonet fighting, and uncomfortable muzzle blast caused by the muzzle's proximity to the operator's head.

Proponents of bullpups have responses to these criticisms, however: The location of the magazine well makes it easier to change magazines while traveling in an open vehicle. The high sight position is a design feature shared with many modern conventional rifles (like the M16), allows comfortable and accurate shooting posture, and is effective in combatting muzzle climb. Further, muzzle blast is actually less in a bullpup rifle than in a conventional rifle of equal overall length and, just as with the bayonet's range, increasing the barrel length is a simple fix, if the problem is deemed serious enough.

Examples of bullpup firearms

* Barrett M90A2 Bullpup, M95
* Bushmaster Arm Pistol, M17S
* Crye MR-C
* DSTO AICW
* Enfield EM2, (RSAF)SA80
* FN F2000, P90
* GIAT FAMAS
* Groza OC-14
* Heckler & Koch G11, LMG11, WSG-2000
* IMI Tavor TAR-21
* Interdynamics MKR
* KBP　A-91
* Korobov TKB-408, TKB-022
* K-Var AKU-94
* Muzzlelite Mini-14, Mini-30
* Norinco 86S
* PRCM QBZ-95, QBZ-97
* SAR-21
* Steyr AUG
* Valmet M82
* Vektor CR-21
* Vepr
* Walther G22, WA2000

Shotgun
* Heckler-Koch CAWS
* Mossberg 500 Bullpup
* NeoStead 2000
* Pancor Jackhammer

Other
* Steyr ACR
* XM25