The Jackhammer is a bullpup automatic shotgun which never entered production, using a revolver-style detachable cylinder (referred to as a "cassette") with a rotating action similar to the British Webley-Fosbery Automatic Revolver, and a gas-seal system similar to that of the Nagant Revolver, though with the barrel moving back to form the seal instead of the cylinder moving forward. A forward-back pump-action forend is used to cock the weapon initially, after which it indexes automatically. The mechanism is indexed by a cam on an operating rod attached to the barrel, which moves in a zig-zag groove to rotate the cylinder to the next chamber with each forward-back motion. The barrel is blown forward by gas tapped from the bore and returned under spring pressure.
It is often seen in video games as a "super shotgun;" the Jackhammer's popularity is due, in large part, to the futuristic look of the weapon, and is sometimes mistakenly described as the only fully automatic shotgun in existence. There is an element of unreality in featuring the Jackhammer in any context, as the weapon never made it past prototype stage; only two guns capable of firing in fully automatic mode were ever made. The real guns had problems with cassette grooves needing to be manufactured to extremely tight tolerances for the weapon to cycle correctly; typically, the full-auto guns could only manage two or three shots sequentially before failing to cycle. The weapon's design was also cumbersome and uncomfortable to shoot. A well-known fact is that more Jackhammers have appeared in any given work of fiction than ever existed in real life.
One unique feature was that the ammunition cassette could theoretically be combined with an additional assembly containing an array of strikers and a pressure plate to turn it into an ersatz landmine, referred to as the "bear trap." The precise utility of this is debatable since the plate was almost as large as another cassette and the "mine" would expend ten rounds to kill one person, even if it was guaranteed someone would actually stand on it. Regardless, only plastic mockups were ever made in order to test the mechanical workings, and no fully functional examples ever existed. Some sources also state that the magazine came loaded and was sealed at the factory meaning that it could not be reloaded with standard shells, however any remaining examples of this Jackhammer are loaded from standard 2 3/4" 12 gauge shells so this idea appears to not have been implemented. Even if this device were implemented and adopted, the 1997 Ottawa Treaty and the voluntary US ban on "persistent" landmines would have soon brought an end to it.
Two pre-production weapons were subject to full destructive testing, and just one functional Jackhammer remains in existence, a heavy toolroom prototype with a cylinder which accepts standard 12 gauge shells. This is not the final version, and among other things requires that the weapon be almost completely dismantled in order to reload it. For a time this weapon was owned by designer John Anderson; it was later sold to a movie armourer and fitted with the handguard grip of an MP5SD since the original smooth forend was thought to be too slick to reliably operate. This modification has followed to certain videogame renditions of the Jackhammer as the weapon has been used as a reference piece. The weapon is currently registered to a collector in New York.
After initial military testing, John Anderson continued development of the Jackhammer into the Mk3-A2 version. This model is the one that most often appears in media, despite being even less "real" than the original. It can be most easily identified by the sight rib, which rather than being a relatively flimsy stamped piece, is now a single piece aluminium casting with a distinct pattern of lightening cuts with a long slot with three circular holes. Only a single example of the Mk3-A2 is known to exist today and is an unfinished non-functional example lacking several key internal components. However, it is legally registered as a machine gun, and would be legal to build into a fully automatic firing example if its owner decided so.
For some reason, the Jackhammer is often claimed to have been featured in films and TV shows, even though IMFDB has not recorded any live-action appearances of the weapon.
The Pancor Jackhammer can be seen in the following video games:
(Designed in 1984 and patented 1987, never produced)
- Type: Shotgun
- Caliber: 12 gauge pre-loaded (production), standard 12 gauge (prototype)
- Weight: 10.1 lbs (4.57 kg), about 14 pounds for toolroom prototype
- Length: 31 in (78.7 cm)
- Barrel length: 20.7 in (52.5 cm)
- Capacity: 10 round pre-loaded ammunition cassette (production), 10-round revolver cylinder (prototype)
- Fire Modes: Semi / Full-Auto
|Game Title||Appears as||Mods||Notation||Release Date|
|Delta Force: Land Warrior||2000|
|Project IGI: I'm Going In||Incorrect 12-round capacity||2000|
|Max Payne||Incorrect 12-round capacity||2001|
|The Sum Of All Fears||12ga Auto SG||2002|
|Project IGI 2: Covert Strike||Incorrect 12-round capacity||2003|
|Rainbow Six 3: Iron Wrath||2003|
|Söldner: Secret Wars||2004|
|Battlefield 2||Incorrect 7-round capacity||2005|
|Conflict: Global Terror||2005|
|The Darkness||Incorrect 64-round (!) capacity||2007|
|Cross Fire||"Jackhammer"||Pre-production model||2007|
|7.62 High Calibre||Jachhammer Mk3A2||w/ optional suppressor||2008|
|Battlefield 3||MK3A1||Back to Karkand expansion,
incorrect 8 and 12-round capacities
|Survarium||Version with MP5SD handguard||2013|
|Ghost Recon: Phantoms||M3A1||shown with railed top||2014|
|Modern Combat 5||With a front magazine.||2014|
|World of Guns: Gun Disassembly||Pancor Jackhammer||2014|
|Counter-Strike Online||PJ Mk3A1||10 round mag||2015|
|Hot Dogs, Horseshoes & Hand Grenades||"Jackhammer"||Version with MP5SD handguard||2016|