The FBI performed a record number of instant background checks on would-be firearm buyers in 2011 as Americans went on an apparent gun-buying spree, new government data show.

During the holiday season, business really picked up: FBI officials say gun dealers requested more than 1.5 million background checks in December and a third of those checks were requested in the last six days leading up to Christmas.

The numbers came as no surprise to Gerald Rutkowski, manager of Dury's Gun Shop in San Antonio, Texas.

"We've been running ahead all year long," Rutkowski told msnbc.com on Thursday. "We've had an increase of 30 percent in sales over the last year, and for us here in Texas, it's a sign of improving economic conditions."

Texas, which ranks No. 2 in population according to the Census Bureau, was No. 2 in the background checks as well, with 1.15 million screening requests in 2011. Kentucky topped the list.

Millions of queries
Nationwide, FBI officials said it fielded nearly 16.5 million queries from firearms sellers last year, checking that customers buying guns did not have criminal records or other red flags that made them ineligible to purchase weapons.

That was up 15 percent from 2010, when the FBI performed 14.4 million screenings using its National Instant Criminal Background Check System, or NICS, and the highest number of annual screenings performed since the checks went into effect in 1998.

The FBI cautioned that each background check did not necessarily represent an individual firearm sale, in part because some would-be buyers fail to pass the screening.

But FBI spokesman Stephen Fischer said the background checks are correlated with weapon purchases. So the spike in screenings last year suggests that an increase in gun sales the agency has been tracking for several years was continuing.

Fischer declined to analyze or comment on the jump in firearms purchases, saying the bureau's responsibility was only "to operate and maintain the NICS system."

But Andrew Arulanandam, a spokesman for the National Rifle Association, said he believed the political uncertainty surrounding next year's general election was prompting would-be gun buyers to accelerate purchases.

Arulanandam said the jump in sales since 2006 largely reflected concern that the Democrats swept into office in recent years, including President Barack Obama, would curb the right to bear arms. That has not happened.

Buying surge since 2006
Purchases of handguns and rifles, which had held steady throughout the early part of the decade, began to surge in 2006 and have nearly doubled since then, according to FBI data. Other figures showed:

• Kentucky, which ranks 26th nationally in terms of population, topped the state rankings for pre-purchase background checks in 2011, the FBI said. Gun sellers in the Bluegrass State, which has just 4.3 million residents, generated almost 2.3 million background checks in 2011 -- accounting for roughly one of every seven the FBI processed during the year.
• Texas was followed by Utah, which accounted for nearly a quarter of the overall increase in checks and sales in 2011.
• Utah is an increasingly popular place for gun owners from all over the country to get concealed-firearms permits because the state's permits are cheap, easy to apply for even if buyers do not live in Utah, and recognized in nearly three dozen other states.

Msnbc.com's Sevil Omer contributed to this report from Reuters.

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