The SPAS-12 was designed in 1972 as a semi-automatic military or law enforcement shotgun, and production began in 1979. The gun's main intended market was in the United States, and importation started in 1982, under F.I.E. In 1989, importation of the SPAS-12 to the US civilian market was restricted under federal law, and sales of the gun were banned.
In 1990, American Arms Inc., bought out all existing SPAS shotguns and spare parts, and began reimportation of the shotgun with the new acronym Sporting Purpose Automatic Shotgun. The gun was redesigned with a synthetic fixed stock and a new 6-round magazine capacity, this would allow the gun to be reimported again until 1994, when then-President Clinton signed the Federal Assault Weapons Ban into law, banning all variants of the SPAS-12.
Due to few civilian and military/law enforcement sales, along with complexity and high-costs to produce the shotgun, Franchi dropped the weapon from its lineup altogether in 2000, with a final price of $1,500 USD during the last year of production for unrestricted sales outside of the United States. In all, out of 37,000 manufactured in total, only 1,850 (or 5%) were exported to the United States from 1982 to 1994.
The SPAS-12 can function on two settings. The first is "automatic" (more accurately, self-loading semi-automatic) - the slide is locked forward and a gas system serves to load the next round without further effort from the operator. In automatic mode, the weapon can fire around 4 rounds per second, one round per trigger pull. The second setting is pump-action - the slide must be manually pumped back and forth after every shot to eject the spent shell and load a new round from the internal magazine. This mode is required to reliably fire low-pressure ammunition such as tear gas rounds or less-lethal bean bags. Switching between firing modes is done by pressing a button under the slide, and moving the slide slightly forwards or backwards until it clicks into position.
The SPAS-12 also has a magazine cut-off feature that, when activated, prevents the loading of a new round from the internal magazine when the slide is opened. This allows the operator to load a specialized round into the chamber without going through the entire magazine first. Early SPAS-12 models also featured a lever-type safety, but it tended to fire the weapon when switch from the "safe" to "fire" position with a round loaded. This was later replaced by a more traditional cross-bolt safety, though most SPAS-12s were never refitted with the redesigned safety, and still have the defective original safety.
- The SPAS-12 is famous for appearing in many films, television, videos games and anime.