Demand for firearms has exploded in the U.S., wiping store shelves clean of guns and ammo in nearly every town, city and state since the school shooting in Connecticut and ensuing calls for stricter gun laws.

Gun retailers as large as Walmart are nearly sold out of every type of firearm, including semiautomatic rifles like the one that 20-year-old Adam Lanza used to kill 20 children and six adults at Sandy Hook Elementary school on Friday.

'It’s a money-grab out there,' Mike McGovern, an IT project manager, told Huffington Post. McGovern said he bought a Glock 19 handgun the morning after the shooting in Connecticut at a packed Western New Jersey gun store.

Smaller retailers are also sold out as Americans panic over calls by President Obama and numerous lawmakers, both Republicans and Democrats, to strengthen the country's gun laws.

John Hotchkiss, owner of Red Bear Gun Brokers in Colorado Springs, Colorado, said his gun inventory is nearly sold out - as are his nearly two dozen distributors.