In real life, the Smith Wesson M76 submachine gun was a weapon for men who fought in the shadows.
Created as a replacement for an embargoed firearm popular with American clandestine operators and special forces during the 1950s and 1960s, it combined a rapid rate of fire with the ability to attach a suppressor.
But the M76 is also a movie gun that Hollywood has generously splashed all over the silver screen.
Some film historians say it earned the honor of being the first "zombie apocalypse gun." Charlton Heston packs one in the '70s cult classic The Omega Man, where his character Col. Robert Neville sprays deranged nightwalkers with automatic fire after bio-warfare wipes out most of the world's population.
The development of the M76 is a story that is part American ingenuity, part Swedish politics, and all about ensuring special operators could continue to use a choice weapon.
The M76 replaced the Carl Gustav M/45 Kulsprutepistol, a 9 x 19 mm submachine gun with a 36-round magazine manufactured in Sweden that was a favorite of covert forces. The M/45 actually was the main submachine gun of the Swedish Army from 1945 until it phased out in the 1990s, but reserve units carried it until 2007.
The Americans who used the weapon began to call it "the Swedish K."
Journalist Michael Herr in his memoir Dispatches describes "Ivy League spooks," CIA agents who carried the Swedish K as their preferred weapon as they drove near the Cambodian border.
Soon, SEALs and Green Berets used the Swedish K because much of their fighting was in the narrow confines of a jungle environment where firepower and maneuverability were more important than range and accuracy.
SEAL team members also liked the fact the Swedish K is an open-bolt weapon, which allowed it to be fired almost immediately after a frogman crossed the beach.
"You could see why it would be preferable to the US Thompson or M-3 Submachine gun," said Alan Archambault, former supervisory curator for the U.S. Army Center of Military History and a retired Army officer. "A friend of mine who served with Special Forces in Vietnam relatively early on told me that by using foreign weapons like the Swedish K it also helped to conceal the US presence a bit. I also think that Special Ops men tend to like unusual weapons rather than using standard US issue weapons."
Light, rugged, capable of firing 550 rounds a minute and unfailingly reliable, Swedish Ks soon became a weapon in the arsenals of covert forces, particularly those operating in Southeast Asia as the United States became more and more involved in what became the Vietnam War.
"I know my friend was proud of using a Swedish K in Vietnam," Archambault said. "It was one more way the Special Forces were set apart from the typical 'line doggies.' It goes along with the Green Beret and other elite designations."
However, in 1966 the Swedish government adopted the position of officially opposing U.S. involvement in the Vietnam War. Pacifist Sweden placed an embargo on military supplies exported to the United States, including the Swedish K.
The decision particularly troubled the U.S. Navy SEALs, who decided to turn to a domestic supplier for a copy of the Swedish K. The Navy approached Smith Wesson and by 1967 the company produced a clone, the M76.
It had all of the good qualities of the Swedish K as well as few refinements including a higher rate of fire (720 rounds per minute). It also could be fitted with the SG9 suppressor.
In addition, Smith Wesson experimented with a version of the M76 that electronically fired caseless ammunition. The gun actually worked well, but the caseless ammo was easily damaged by rough handling so the project was scrapped.
M76s found their way into the hands of SEAL team members and some Green Berets, where they are were used successfully during many covert operations. But as the Vietnam War began to wind down demand for the weapon decreased; more powerful weapons soon replaced it.
By 1974, Smith Wesson ceased production of the M76. However, the weapon remained in use in the Navy, where it was still used in some instances by SEAL teams or it was issued to helicopter pilots for self-defense in case of a crash landing.
Law enforcement agencies also purchased the weapon. In fact, the September 11, 2001, terrorist attack on the World Trade Center destroyed a cache of M76s where New York state law enforcement agencies maintained an arsenal.
There was even an attempt to revive the weapon during the 1980s. In 1983, Mike Ruplinger and Kenneth Dominick started a company called MK Arms after acquiring the rights to the M76 from Smith Wesson. The company manufactured both new weapons and replacement parts for existing M76s that were still in military and law enforcement inventories.
However, the M76 gained new life as a movie weapon where it was featured prominently not only in the films already mentioned but also Magnum Force, The Taking of Pelham One Two Three, Dog Day Afternoon and Black Sunday.
But perhaps it is in The Omega Man where the M76 gets the most screen time.
Not only does a leisured-suited, eight-track-tape-playing Charlton Heston have one in hand during almost every scene, the weapon used in the film introduces an innovation: the tactical light. In several scenes, the movie's armorer used C-clamps to attach a flashlight to the gun's barrel so Heston could hunt the film's nightwalkers more efficiently.