Sorry, California. You're going to have to find another way to defend yourself from a violent assault. Gunmakers Sturm, Ruger (NYSE:RGR) and Smith & Wesson (NASDAQ:AOBC) have said that due to the "microstamping" law the state legislature approved, they will no longer sell semiautomatic guns in the Eureka state. Maybe you can use a pair of scissors as the Department of Homeland Security recommends you do in a mass shooter situation.

Microstamping is the process of embedding a unique code on the firing pin of a gun that would be "stamped" on a casing when it is fired. Think of it like a fingerprint for bullets. While it sounds great in theory, as it would allow a bullet to be traced to a particular gun and so back to its owner, presumably still holding the literal "smoking gun," there are a raft of practical problems with the law. For example, revolvers don't eject casings like semiautomatics do, so once all the rounds in the cylinder are spent, you manually remove them and leave not a trace. It's why they're not covered by the new California law and why Smith & Wesson will still sell them there, meaning only the newest, most advanced weapons in terms of production, safety, and use will be banned.

The process is also not as simple as laser-etching a code on a firing pin, but rather involves individualization for each model of gun since not all parts are the same, making it an exorbitantly expensive procedure. Moreover, the durability of the engraving on the firing pin is questionable, with even the person holding the patent on microstamping being forced to admit it's something of a hit-or-miss effort in getting a readable code to print on a casing.

Last, although hundreds of millions of guns have been manufactured, only a tiny percentage have been used in crimes, and of that small number, a good 10% to 15% were stolen. Furthermore, the Justice Department found in one study that of the criminals caught in possession of a handgun, more than a third of them obtained them through illegal means, suggesting a sizable portion of all guns used in crimes won't be traceable regardless of what is stamped on them. Not to mention that swapping out an etched firing pin for one that doesn't contain markings isn't an overly complicated process.

In truth, microstamping is really a Trojan horse for gun control. By necessity, it would mean a centralized database for the registration of all the microstamp codes issued, and then gun owners would be required to register every gun they own with the government so they could be traced. Ultimately, those guns for which the tracking wouldn't work would likely be banned.

With that as the backdrop, it's understandable why gunmakers are walking away from or reducing their presence in states hostile to ownership. Manufacturers have been pulling up stakes across the country as some states seek to enact laws that unduly restrict or ban the manufacture, sale, and legal ownership of weapons. Earlier this month, Magpul Industries made good on its promise to evacuate from Colorado following that state's passage of laws that made it illegal to own the type of product it was manufacturing, while PTR Industries voted with its feet and is leaving Connecticut over restrictive laws passed in the wake of the Sandy Hook school shooting.

Although some manufacturers have opted to stay in their home states, they're expanding to meet the growing demand for guns by building factories in gun-friendly states. Ruger is staying put in Connecticut, but its first expansion in 25 years is at a factory being built in North Carolina. New York-based Remington Arms is considering building new facilities in Tennessee, and Beretta, while not leaving Maryland yet, says if it does expand, it won't be somewhere that hasn't "shown consistent, strong support for Second Amendment rights."

Gunmakers like Smith & Wesson and Sturm, Ruger are fighting the law along with the NRA, National Shooting Sports Foundation, and other gun rights groups. But the sun is setting on California as a place to protect yourself with state-of-the-art weaponry.