Paul M. Barrett recounts the story of Gaston Glock, the man behind the world-famous gun. How an attempt to regulate it failed:
[T]he magazine-capacity law worked in Glock’s favor. First, the law contained a loophole: All guns and magazines manufactured before the effective date in 1994 were "grandfathered" in. So Glock ran the factory at full tilt and built up a huge inventory of "pre-ban" product. When the ban took effect, the price of those guns skyrocketed, leading to huge profits for Glock.
Second, Glock was able to continue to sell to the police, who were not covered by the assault-weapons ban. Third, Glock frequently did trade-in deals with police departments which resulted in former police weapons ending up on the used-gun market. Fourth, Glock introduced several smaller models, known as Pocket Rockets, which complied with the ammo restriction. In the end, the legislative attempt to stifle Glock and its large magazines had very little effect. Then, in 2004, the law expired by its own terms, and the NRA blocked its extension. Today, Glock can once again sell pistols with as many rounds as its customers might want.