A customer looks at a custom made AR-15 style rifle at Davidson Defense in Orem, Utah on Feb 4, 2021. (GEORGE FREY / AFP)

"We can't keep guns on the shelf," Charles Weston, owner of Drum Magazines in Kansas, Missouri, said of the rush on sales since the riot at the US Capitol on Jan 6 that left five people dead, including a Capitol Police officer.

Gun sales often rise during presidential election years amid worries a new administration could change gun laws

Gun sales in the United States hit a historic high of 2 million in January－also the month President Joe Biden took office. The figure extended a record-setting surge that began when the coronavirus pandemic took hold in early 2020.

"Guns, ammunition, any extra accessories. Any optics. Anything that's going to give that advantage. Trying to buy bulletproof vests, even gas masks," Weston told NBC affiliate KSGB-TV.

Weston said his customers are not acting out of fear, but preparation.

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Trin Porter agrees. He said being prepared was the goal for his family after watching the attack inside the Capitol in Washington.

"If they can do it at the US Capitol, anybody can decide to have an insurrection anywhere. And with that being said, everybody needs to be able to protect themselves," he said.

Gene Smith, co-owner of Hoover Tactical Firearm in Birmingham, Alabama, said his store has been crowded with customers since the day after the riot by supporters of then-president Donald Trump forced lawmakers and then-vice president Mike Pence to flee the Capitol as they were voting to affirm Biden's electoral victory.

For the three days after the riot, Smith said: "We'll probably do over $100,000. That is very atypical."

Smith, who could not be reached to confirm sales for those days, told Fox affiliate WBRC-6 TV that about 40 percent of his business can depend on what is going on nationally.

"I like the attention, but I don't like the issues that created the attention toward firearms," he said. "I think some people are overreacting."

The sales of 2 million firearms last month marked a 79 percent increase over the same month last year and set a record for January, according to the National Shooting Sports Foundation, or NSSF, an industry trade group. Michigan and New Jersey recorded the biggest percentage change in firearm purchases in January compared with the previous year, at more than triple the national rate.

The FBI reported that background checks for firearms purchases exceeded 4.31 million in January, the largest monthly tally since the bureau started keeping track.

On the day of the Capitol riot, the FBI said it conducted 170,000 background checks, followed by 524,000 more over the next three days.

Social unrest concerns

The fear of social unrest after the riot played a role in January's sales, according to another firearms trade group, Small Arms Analytics and Forecasting.

"Everybody in America is buying these guns," said Mark Oliva, public affairs director for the NSSF. "I'm a 47-year-old white guy living in the suburbs of DC. It's not just people like me."

People saw the storming of the Capitol and became very concerned for their safety, he said.

US arms sales soared last year as the pandemic took hold. Estimated firearm purchases climbed to 2.1 million in March, early in the pandemic when cities and states issued stay-at-home orders.

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The killing of African American George Floyd during an arrest by a white police officer in Minneapolis in May 25 last year set off a summer of racial justice protests. Firearms sales rose further, to 2.8 million in June and 2.5 million in July.

Gun sales often rise during presidential election years amid worries a new administration could change gun laws.

Biden, a Democrat, has supported gun control measures such as a ban on assault weapons.

On Thursday, White House press secretary Jen Psaki said Biden "would love to see action" on gun control.