Pancor Jackhammer Mk3A2 | |
---|---|
Type | Bullpup revolver automatic shotgun |
Place of origin | United States |
Production history | |
Designer | John Anderson |
Designed | 1984 |
Manufacturer | Pancor Corporation |
No. built | 3 (2 were destroyed in testing) |
Specifications | |
Mass | 7.9 kg (17 lb) |
Length | 787 mm (31.0 in) |
Barrel length | 525 mm (20.7 in) |
Cartridge | 12 gauge 2+3⁄4 in (70 mm) |
Action | Gas-operated, revolving cylinder |
Rate of fire | 240 rpm |
Feed system | 10-shot detachable cylinder |
Sights | Iron sights |
The Pancor Corporation Jackhammer is a 12-gauge, blow-forward gas-operated bullpup automatic shotgun designed in 1984 and patented in 1987. Only three working prototypes of the Jackhammer were built. Nonetheless, its distinctive aesthetics and futuristic design have made it a prop in action films[ citation needed ], television programs[ citation needed ], and video games.
The Jackhammer was designed by John A. Anderson, who formed the company Pancor Industries in New Mexico. Anderson designed it based on his experiences using pump action shotguns in the Korean War and believed he could create a better shotgun, finding reloading pump action shotguns awkward and time consuming. [1] Reportedly, several foreign governments expressed interest in the design and even ordered initial production units once ready for delivery. [1] However, export of the design was held up for production due to United States Department of Defense testing, though the design was eventually rejected.
Testing was done by HP White Labs in destructive tests (destroying two of the three produced). Those sent to HP White Labs reportedly had 4 lb (1.8 kg) of material removed with increased stamping instead of casting and a different easier method of reloading. Thus the sole surviving example is not indicative of what would've been an actual production model and is better considered a tool room prototype. Several dozen non-functioning examples were made from sheet tin, balsa wood, and clay in order to make working tool prototypes.
Civilian sales were made impossible by the classification in the US of the Jackhammer as a machine gun and restrictions on machine gun manufacture enacted in 1986. Additionally those foreign governments that did express interest were unwilling to finance development and final production. [1] With no customers and little interest, Pancor went bankrupt. Supposed overseas orders were subject to United States Department of State approval that was not forthcoming. The assets of Pancor were sold off, including the few prototypes built. [1] [2]
A toolroom prototype that is in technical firing condition, but is constructed largely with machine screws and requires disassembly to reload, was owned by Movie Gun Services, during which its forearm was replaced with an MP5SD handguard. [1] This example has since been auctioned. [3] Another prototype with more refined construction, though non-functional, was legally registered as a machine gun and has also been seen auctioned. [4] [5]
Though unconventional, the Jackhammer can best be described as a gas-operated revolver. Many parts were constructed of Rynite polymer to reduce weight. Layout was of a bullpup configuration with a 10-round revolving cylinder that fired conventional, 12-gauge shells. The cylinder's method of rotation was very similar to the Webley–Fosbery Automatic Revolver, an operating rod being used to rotate the cylinder, [6] although gas-operated as opposed to the recoil operation of the Webley-Fosbery.
The Jackhammer is capable of semi-automatic and fully automatic fire by way of a thumb safety/selector switch. [1] At the moment of firing, the front of the shell sealed inside the breech of the barrel much like the Nagant M1895 revolver. Unlike the Nagant, whose cylinder moved forward to form the seal, the barrel of the Jackhammer was driven forward and away from the cylinder by a ring-piston, using gas tapped from the bore. As the barrel moved forward, the breech cleared the front of the fired cartridge and an operating rod attached to the barrel rotated the cylinder through a "zig-zag" cam arrangement. As the next shell aligned with the bore, the barrel returned under spring pressure back into the front end of the cylinder. Spent shells were retained in the cylinder, as in a traditional revolver. The Jackhammer has a charging handle in the forward grip to charge the weapon and a cocking lever in the buttstock to recock the firing mechanism in case of light strikes to the primer. [1] For reloading, the cylinder was removed from the bottom of its housing and shells were manually extracted. Removing the cylinder required the barrel be moved and secured in the forward position. [6]
Unique to the Jackhammer was the ability to convert a loaded cylinder from the weapon into an anti-personnel device similar to a land mine by the addition of a firing mechanism. The cylinder would be loaded with up to ten 12-gauge shells and the firing mechanism fitted over the bottom section of the cylinder. A pressure plate or plunger can then set to mechanically fire the shells in the cylinder upon pressing or initiate a spring-loaded timer which can be set to trigger firing up to twelve hours later, in one hour intervals. As the cylinder is designed to contain the pressure of firing normally, it can be discharged and reused when used in Bear Trap configuration. [7]
There is some disagreement over whether working models of the Bear Trap were built. According to Ian McCollum of Forgotten Weapons , no working prototypes were produced, however plastic model prototypes were produced and reportedly worked well. [1] However, according to Jane's, development of the Bear Trap was fully completed as of 1994. [7] [ page needed ]
A firearm is any type of gun that uses an explosive charge and is designed to be readily carried and used by an individual. The term is legally defined further in different countries.
A revolver is a repeating handgun that has at least one barrel and uses a revolving cylinder containing multiple chambers for firing. Because most revolver models hold up to six cartridges, before needing to be reloaded, revolvers are commonly called six shooters.
In firearms terminology, an action is the functional mechanism of a breech-loading firearm that handles the ammunition cartridges, or the method by which that mechanism works. Actions are technically not present on muzzleloaders, as all those are single-shot firearms with a closed off breech with the powder and projectile manually loaded from the muzzle. Instead, the muzzleloader ignition mechanism is referred to as the lock.
A semi-automatic pistol is a handgun that automatically ejects and loads cartridges in its chamber after every shot fired. Only one round of ammunition is fired each time the trigger is pulled, as the pistol's fire control group disconnects the trigger mechanism from the firing pin/striker until the trigger has been released and reset.
A repeating rifle is a single-barreled rifle capable of repeated discharges between each ammunition reload. This is typically achieved by having multiple cartridges stored in a magazine and then fed individually into the chamber by a reciprocating bolt, via either a manual or automatic action mechanism, while the act of chambering the round typically also recocks the hammer/striker for the following shot. In common usage, the term "repeating rifle" most often refers specifically to manual repeating rifles, as opposed to self-loading rifles, which use the recoil, gas, or blowback of the previous shot to cycle the action and load the next round, even though all self-loading firearms are technically a subcategory of repeating firearms.
The Mateba Model 6 Unica is a recoil operated semi-automatic revolver, one of only a few of this type ever produced. It was developed by Mateba, based in Pavia, Italy. Inventor Emilio Ghisoni (1937–2008), who was also famous for later designing the Chiappa Rhino, is listed as the owner of U.S. Patent 4,712,466 which details the operation of the weapon.
An automatic revolver also known as semi-automatic revolver, is a revolver that uses the recoil energy of firing for cocking the hammer and revolving the cylinder, rather than using manual operations to perform these actions. As semi-automatic firearms, the shooter must manually operate the trigger to discharge each shot.
Gas-operation is a system of operation used to provide energy to operate locked breech, autoloading firearms. In gas-operation, a portion of high-pressure gas from the cartridge being fired is used to power a mechanism to dispose of the spent case and insert a new cartridge into the chamber. Energy from the gas is harnessed through either a port in the barrel or a trap at the muzzle. This high-pressure gas impinges on a surface such as a piston head to provide motion for unlocking of the action, extraction of the spent case, ejection, cocking of the hammer or striker, chambering of a fresh cartridge, and locking of the action.
The Webley–Fosbery Self-Cocking Automatic Revolver is a recoil-operated automatic revolver designed by Lieutenant Colonel George Vincent Fosbery VC and produced by the Webley & Scott company from 1901 to 1924. The revolver is easily recognisable by the zig-zag grooves on the cylinder.
The Nagant M1895 Revolver is a seven-shot, gas-seal revolver designed and produced by Belgian industrialist Léon Nagant for the Russian Empire.
Break action is a type of firearm action in which the barrel(s) are hinged much like a door and rotate perpendicularly to the bore axis to expose the breech and allow loading and unloading of cartridges. A separate operation may be required for the cocking of a hammer to fire the new round. There are many types of break-action firearms; break actions are universal in double-barreled shotguns, double-barreled rifles, combination guns, and are commonly found in single shot pistols, rifles, shotguns, including flare guns, grenade launchers, air guns, and some older revolver designs. They are also known as hinge-action, break-open, break-barrel, break-top, or, on old revolvers, top-break actions.
A pistol is a type of handgun, characterized by a barrel with an integral chamber. The word "pistol" is derived from the Middle French pistolet, meaning a small gun or knife, and first appeared in the English language c. 1570 when early handguns were produced in Europe. In colloquial usage, the word "pistol" is often used as a generic term to describe any type of handgun, inclusive of revolvers and the pocket-sized derringers.
In firearms, the cylinder is the cylindrical, rotating part of a revolver containing multiple chambers, each of which is capable of holding a single cartridge. The cylinder rotates (revolves) around a central axis in the revolver's action to sequentially align each individual chamber with the barrel bore for repeated firing. Each time the gun is cocked, the cylinder indexes by one chamber. Serving the same function as a rotary magazine, the cylinder stores ammunitions within the revolver and allows it to fire multiple times before needing to reload.
The following are terms related to firearms and ammunition topics.
An automatic shotgun is an automatic firearm that fires shotgun shells and uses some of the energy of each shot to automatically cycle the action and load a new round. It will fire repeatedly until the trigger is released or ammunition runs out. Automatic shotguns have a very limited range, but provide tremendous firepower at close range.
The Mauser C78 - also known as M78 Oberndorf - is a single-action revolver manufactured by the Mauser company in Oberndorf am Neckar during the late 19th century. It was the first German revolver to be mass-produced for modern center-fire cartridges. It was also called the "zig-zag" in reference to the design of the six-round zig-zag-grooved cylinder and was chambered in various 6 mm to 11 mm calibers.
The Winchester Liberator was a prototype 16-gauge, four-barrelled shotgun, similar to a scaled-up four-shot double action derringer. It was an implementation of the Hillberg Insurgency Weapon design. Robert Hillberg, the designer, envisioned a weapon that was cheap to manufacture, easy to use, and provided a significant chance of being effective in the hands of someone who had never handled a firearm before. Pistols and submachine guns were eliminated from consideration due to the training required to use them effectively. The shotgun was chosen because it provided a very high volume of fire with a high hit probability.
Recoil operation is an operating mechanism used to implement locked-breech autoloading firearms. Recoil operated firearms use the energy of recoil to cycle the action, as opposed to gas operation or blowback operation using the pressure of the propellant gas.
The Landstad revolver was an automatic revolver of Norwegian origin. The weapon had an unusual feeding device that used both a 2 round cylinder and a grip inserted magazine.
A repeating firearm or repeater is any firearm that is capable of being fired repeatedly before having to manually reloaded with new ammunition into the weapon.