Sturm, Ruger said a 50 percent increase in sales went back to President Obama's re-election campaign, when gun owners began to fear some guns would so be harder, or impossible, to buy. - 

Sturm, Ruger, the publicly traded gun maker, reported a 50 percent increase in sales for 2012. Most of that increase came before the school massacre in Connecticut in December. Sturm, Ruger's CEO, Mike Fifer, told analysts the surge resulted in part from the "current political environment" beginning with President Obama's re-election campaign.

Fifer told analysts today he wishes the Connecticut-based company had amassed a bigger inventory. "We would have sold all of it and then more. But we didn't. And so, all we could sell is what we could make each week."

Fifer says Sturm, Ruger won't be able to build up that inventory for a while now, at least until demand slows down. By the end of last year, it had a backlog a million and a half guns long.

Rommel Dionisio is a firearms analyst with Wedbush Securities. He says that, when it comes to growth, gun makers are very cautious. "One of the real hesitations on the part of the manufacturers to build capacity is the realization that the surge is not going to be that sustainable," he said.

It's also hard for suppliers to keep up with new demand. Gun sales spiked when Bill Clinton was elected, and when Barack Obama became president. Dionisio says that, in both those cases, gun sales came to a halt one year later. By then, everyone had all the guns they wanted.

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