Are many people surprised by this new report from Bloomberg News?

After a Glock-wielding gunman killed six people at a Tucson shopping center on Jan. 8, Greg Wolff, the owner of two Arizona gun shops, told his manager to get ready for a stampede of new customers.

Wolff was right. Instead of hurting sales, the massacre had the $499 semi-automatic pistols— popular with police, sport shooters and gangsters— flying out the doors of his Glockmeister stores in Mesa and Phoenix.

"We're at double our volume over what we usually do," Wolff said two days after the shooting spree that also left 14 wounded, including Democratic Representative Gabrielle Giffords, who remains in critical condition.

A national debate over weaknesses in state and federal gun laws stirred by the shooting has stoked fears among gun buyers that stiffer restrictions may be coming from Congress, gun dealers say. The result is that a deadly demonstration of the weapon's effectiveness has also fired up sales of handguns in Arizona and other states, according to federal law enforcement data.

"When something like this happens people get worried that the government is going to ban stuff," Wolff said.

Without ever announcing a major new handgun control initiative, Barack Obama briefly sparked a boom in the gun industry. In summer 2009 the London Telegraph declared the new president "is turning out to be one of the best firearms salesman in American history," just on the suspicion that he was going to take action, as though he didn't have more than enough controversy on his hands with health care. Dealers welcomed a new speculative cohort:

Sales of high-end collectible rifles, which cost several thousand dollars, have fallen as the recession has deepened. But the value of military-style rifles such as the AR-15, a semi-automatic civilian variant of the US military's fully-automatic M-16, had increased by at least 25 percent.

This has made modern rifles a potentially lucrative investment. Some people are banking on Mr Obama introducing gun control legislation, a move that would lead to a hefty profit as demand soared and people scrambled to beat a ban on purchases.

More recently the Obama gun bubble appeared permanently deflated, as the Mediamatters.org blog reported in December:

[A]s people have realized that the Obama administration has no covert plans to institute sweeping gun seizures, gun sales have fallen dramatically. In addition, executives say that many of the guns bought in reaction to Obama's election are now being re-sold on the secondary market, further depressing new gun sales. Public-earnings calls by two industry leaders detail the magnitude of the fear-based bubble that was created and perpetuated by the conservative media.

In this case at least, President Obama's often-criticized moderation made sense. But there's always the risk that new well-intentioned measures could spark another preemptive buying spree, this time possibly focused on semiautomatic pistols. That's unlikely given the new Congress, but even a debate may induce a new round of proliferation.

Of course the firearms industry, too, isn't always the best advocate of its own cause. A current Glock Facebook page, dating from last April, reviews the enthusiasm of police departments for its new products and then adds:

GLOCK, Inc. also strives to serve the expanding consumer market by providing safe, simple and fast products—giving our customers a customizable solution that provides the confidence necessary to succeed and survive in any situation.