America's oldest gunmaker, Remington, has filed for bankruptcy protection and Donald Trump is partly to blame.

Key points: Gun sales increase when Democrats are in power

Gun sales increase when Democrats are in power Many stores had prepared for an increase in gun sales expecting a Hillary Clinton election win

Many stores had prepared for an increase in gun sales expecting a Hillary Clinton election win Double-barrel rifles are among new guns that companies hope will attract more buyers

The company's problems started long before the recent calls for tighter gun control in the wake of the Parkland shooting in Florida last month.

The company said sales fell significantly in the year before it filed for Chapter 11 bankruptcy.

Some are calling it the "Trump slump".

"When there is a Democratic president and a Democratic Congress, there is more fear that gun control will pass and therefore firearms will be harder to obtain, as a result people rush out, they buy more guns," said Polly Mosendz, firearms industry reporter for Bloomberg News.

"When there is a Republican Congress that fear-based buying largely disappears."

Not only are people buying fewer firearms, some US gun stores have a backlog of stock.

Sorry, this video has expired Tens of thousands of people rallied across the US on the weekend for tighter gun laws (Photo: AP/Jose Luis Magana)

The anticipation of Hillary Clinton winning the election led many to believe fear-driven sales would spike.

"When she did not win the presidency a lot of stores were stuck with pretty serious inventories," Mosendz said.

"They had all these guns but they didn't have a tonne of buyers.

"When you have that happening you are not going to go to your Remingtons and Smith and Wessons of the world and place huge inventory reorders, you are going to try and sell through what you have as a retailer."

Sales spike after mass shootings

While gun purchases can stall when Republicans are in power, they often spike after mass shootings when calls for stricter gun control get louder.

The US does not collect data on gun sales, but the FBI does monitor the number of background check applications from gun buyers.

Ms Mosendz said according to FBI data, in the month since the Parkland attack, there has been a slight increase in background checks for long gun purchases nationwide, and a higher increase in Florida where the shooting occurred.

"Basically the politicians, by talking about restricting firearms, have encouraged people to go and buy them while they still have the opportunity to buy them," said Jim Snyder from the pro-gun Virginia Citizen Defence League.

"I think that applies to anything — if all of a sudden the government was going to ban, or people thought they were going to ban pick-up trucks I bet the sales of pick-up trucks would go sky high."

When gun buyers are not motivated by fear, companies are always looking for new ways to attract customers.

The Gilboa Snake's double trigger means it can fire two bullets at the same time. ( Supplied )

Gun store websites are offering pre-orders of the Gilboa Snake — a double-barrelled version of the AR-15, the semi-automatic rifle which has become the mass shooter's weapon of choice. The Snake's double trigger means it can fire two bullets at the same time.

"Firearms manufacturers are creative," Mosendz said.

"They are always trying to come out with something new, something interesting, something that is going to get people to buy more guns."

While it's unlikely to be the purchase of choice for a first-time gun buyer, the target market is more likely America's gun "super owners" — people who own an average of 17 guns.

"If you own 17, getting you to buy your 18th is quite difficult, it needs to really offer something that none of your other 17 firearms can do," Mosendz said.