"The Baddest Shotgun in the World"
What manner of scattergun do you think would best fit this definition? Shotguns are horrendous weapons, and a great many tactical autoloaders are in circulation (such as those marketed by Benelli, Heckler & Koch, and Scattergun Technologies), which are commonly fitted with accessories to increase their lethality (short barrels, magazine extensions, folding stocks, tactical lights, or "duckbill" chokes), but as these are considered to be the "industry standard," they shall not be discussed further.
What about the sawed-off double-barreled 10 gauge? Break-action shotguns can be cut down to about a foot in overall length (although they are usually cut back only to the forearm, leaving a pair of 10" barrels with an overall length of about 16"), and it is quite unsettling to find yourself staring into a pair of 1" bores even if you know the weapon is unloaded! With dual hammers cocked back, both barrels can fire simultaneously a discharge easily capable of literally cutting a man in half at point blank range. Loaded up with magnum buckshot, this weapon is like a handheld claymore mine but it is not the baddest shotgun in the world.
The Striker-12 is a high capacity short-barreled shotgun. It has a twelve-shot rotary cylinder, and will fire a round with each pull of the double-action trigger. A version with a legal 18" barrel (the Streetsweeper) was made available to the civilian market for a few years, before the wussies in Congress decided it was too fearsome a weapon to be left unregulated. It is now designated as a Class III "destructive device," and it is illegal to transfer one to another individual without first notifying BATF and paying a $200 Federal tax. Fearsome as it may be, this South African crowd pleaser also is not the baddest shotgun in the world.
The Atchisson Assault-12 is a select-fire short-barreled shotgun with a detachable 20 round drum magazine. It was one of only a very few full-auto shotguns which ever made it past the prototype stage and into production. It was intended specifically for special operations, and saw action with both the SEAL teams and Special Forces during the Vietnam conflict. Today, this nearly uncontrollable killing machine can be found in the arsenal of many SWAT teams (although it usually serves only as a showpiece in these politically correct times). While this fine weapon would be the pride and joy of many collectors, it too fails to meet our criteria for being the baddest shotgun in the world.
In our humble opinion, the shotgun we feel is most deserving of this title is the KS-23M. This awesome weapon, at first glance, appears to be merely another short-barreled pump shotgun fitted with a pistol grip but then one notices that it is twice the size of any other "cruiser-style" shotgun ever seen! This super-sized scattergun looks like the crude renderings of military weapons depicted in action/adventure comic books. That is because it has a 23mm bore (which would make it a 6 gauge) literally double the size of the 12 gauge commonly used by military and law-enforcement personnel. Manufactured by the Soviet company TsNIITochmash, the K-23M Drozd (Thrush) short-barreled 6-gauge is commonly employed by SPETsNAZ and MVD forces.
The recoil of this weapon is incredible, and it can fire a variety of shells, including: buckshot, tear gas, rubber bullet, and anti-vehicular projectile; furthermore, two different kinds of muzzle-mounted grenade launchers are available, which can enable this formidable weapon to fire various types of grenade.
Most commonly seen is the standard version, which employs the underbarrel tubular magazine (3 round capacity + 1) found on most conventional pump shotguns; however, a detachable magazine version is also known to exist. This detachable magazine version (capacity unknown, due to Soviet secrecy) easily qualifies as "the baddest shotgun in the world" (due to its incredible recoil, along with other factors, it is highly unlikely that an autoloading version of this weapon exists).
For more information about the KS-23M, as well as many other declassified "secret weapons" of the former Soviet Union, we highly recommend the definitive work: The New World of Russian Small Arms & Ammo, by Charlie Cutshaw (Paladin Press, 1998).