The Kel-Tec KSG was developed as a traditional manually-actuated, pump-action slide 12-gauge shotgun with several key differences from the normal approach. Firstly, it is arranged in a bullpup configuration which sets the action rear of the pistol grip. This allows for the weight of the gun to be massed at the shooter's shoulder while also allowing retainment of a full-length barrel for a more compact overall package. Secondly, the weapon feeds from two tubular magazines set under the barrel, allowing the shell count to be nearly double the standard offering seen in such weapons. The KSG is produced by Kel-Tec CNC Industries, Incorporated of Florida which also markets a line of pistols and rifles. The twin-tube shotgun was unveiled in 2011 and several variants have emerged since.
The weapon sports a very clean design appearance with sharp lines throughout and available in a variety of finishes beyond the typical black. Its bullpup arrangement means that the stock houses the main internal working components as well as the feed and ejection port and is fixed as an integral component of the gun. At the rear of the buttstock is a recoil pad to help retard some of the violent recoil forces at play. The pistol grip is underslung in the usual way and the gun exhibits an empty weight of 7lbs with a loaded weight of 8.5lbs. Overall length is 26 inches with its barrel measuring 18.5 inches long. Sling loops are standard for transporting the gun on marches. Breakdown of the weapon is handled by management of several pins found about the shotgun's design - making access for repair and cleaning a relatively easy affair. There is a section of Picatinny rail over the barrel and over the tubular magazine pairing - the under-barrel span allows for the fitting of a foregrip or aiming/lighting accessories while the upper span can be used to fit iron sights or various optics. Construction of the weapon includes plastic and steel. The magazine tubes are welded to the design as a permanent fixture.
Supporting 12-gauge shells, the KSG's twin-tube design allows for six (3") or seven (2.75") shells to be loaded into each magazine tube. The firearm is loaded from the bottom through a port at the stock underside which also serves as the ejection port. With another shell chambered ready-to-fire, the total shot count can reach thirteen/fifteen depending on shell size used. The gun feeds from either tube magazine with management, by the operator, of a selector switch near the pistol grip - allowing for feeding from one tube over the other.
The KSG was initially released through a first generation model. A second generation design followed with revisions to counter notable jamming issues and some breakages - a trigger reset was implemented for improved continuous fire and ammunition indicators were added as cut-out ports along the sides, top, and bottom of the magazine tubes. An easier-to-use (and reach) ambidextrous release lever was also added.
Major versions beyond the standard KSG (18.5" barrel, 26" length, 6.9lb weight, 7+7+1 feeding with 2.75 shells) are the "KSG Patrol" and "KSG Tactical". The KSG Patrol form is given a 16.1" barrel length while showcasing a 24 inch overall length, 6.7lb weight and 6+6+1 shell capacity. The KSG Tactical features a 13.7 inch long barrel with 21.4 inch overall length and 6.2lb weight. Shell count is 5+5+1.