The famous "Bowling Bullet"
There is more truth to mgjohn's posting than he may have realized. It wasn't the guns, but rather the target seeking ammo that they used. These rounds were invented in 1947 by Carl Elwood Bowling in Garden Grove, California. In 1948, having completed ballistic and target acquisition testing, Bowling opened a small factory in Culver City, California, virtually in the shadow of the now-defunct MGM Studios. As with many inventors, Bowling was under-capitalized and struggled to bring his product to market. Unfortunately he was not successful and filed for bankruptcy in November of 1948, five months after opening his Culver City factory. In February of 1949 the contents of the factory were sold at public auction and all of the prototype and first run ammunition was acquired by Martin Retting. Some of this ammo was purchased from Retting by the armorer at MGM Studios. Impressed with the results, but unaware that there would be no more of it ever produced, he arranged to demonstrate it to a select group of studio executives and members of the Directors Guild. Both groups were highly impressed, and left the demonstration convinced that Bowling's Sure Shot ammo would be used by law enforcement officers everywhere. To ensure that future films and television programs would not only be entertaining, but technically accurate, they decided to depict cops using "Bowling's Bullets" in all of their productions.
And what of Carl Elwood Bowling? Following the failure of his Culver City ammunition factory he went on to invent an automobile engine that delivered more than 100 miles-per-gallon when fitted to a 1950 Packard. The rest is history.