Sales of firearms have rocketed in the United States since the school massacre in Connecticut, amid fears certain assault weapons and high-capacity magazines could be banned.
A semi-automatic Bushmaster AR-15 assault rifle was used in the Sandy Hook Elementary School massacre in which 20 children and six adults were shot and killed on 14 December by a man who shot his mother first, before taking his own life.
Larry Hyatt, owner of a gun shop in Charlotte, North Carolina, described the rush as largely "politically motivated".
"We have been in business for 50 years, and we have seen (fear-based buying) before," he said.
"But this is more intense because the president got in the media and basically said, 'if you want a gun, you better get it now'."
AAP reports yearly sales of guns and ammunition are estimated at about $US7 billion in the United States.
Newspapers in rural areas report a roaring pre-Christmas trade in guns and magazines, especially at gun shows, which often don't require buyers to undergo any background checks.
AAP reports there were an estimated 310 million non-military firearms in the United States in 2009.
There have been 62 mass shooting incidents in the US since 1982. The majority of weapons used were semi-automatic handguns and rifles obtained legally by the killers.