The Harper government, which has championed the rights of gun owners for years, is reviewing a decision by the RCMP to effectively ban a previously legal rifle.
The National Firearms Association said the Mounties have reclassified the Swiss Arms Classic Green carbine as a prohibited weapon, essentially banning it.
The move isn't sitting well with owners.
Gun collectors such as Greg Dunn from Calgary say the rifle is a piece to be proud of.
"They're high-end collectors rifles, they're valued between $3,500 and $4,000 each," he said.
"There's never been an incident where one's been used in a crime of violence as far as I know in the last decade."
Legally sold for a decade
Alberta Tory MP Chris Warkentin raised the issue in question period Friday, saying the rifles had been legally sold for a decade.
MP Roxanne James, who represents the riding of Scarborough Centre and serves as parliamentary secretary to the public safety minister, said the government is troubled by the ruling and will review what she called "an unfortunate decision."
She said a number of options are being explored.
The issue is a tricky one for Prime Minister Stephen Harper's government, which campaigned for years to eliminate the long-gun registry and even went to court to keep Quebec from holding on to existing records from the registry.
"We are in fact very troubled by the situation that has arisen from the Swiss Arms rifle," James told the House of Commons. "This decision was made by bureaucrats and not by politicians."
Hundreds of rifles in Canadian hands
The firearms association said in a statement that there are 1,000 to 1,800 of the rifles in Canadian hands.
"The government will not be offering compensation and will be demanding that the firearms, which cost between $3,000-$4,000 be surrendered," the statement said. "The government is suggesting that all affected firearms owners contact the distributors from which the firearms were purchased for reimbursement."
J.R. Cox, who operates a gun shop called The Shooting Edge in Calgary, owns 10 of the guns and has about 15 for sale in his store.
He worked with RCMP more than a decade ago to have the guns approved in Canada.
"Numerous RCMP committees looked at this, approved it and said it was fine and now 12 years later they're saying it's not."
Modified version already banned
He said the trouble began when modified versions of a similar gun manufactured by Swiss Arms appeared in Canada about eight months ago.
Those guns, he said, were used models that are banned in Canada but were purchased in Switzerland, shipped to Canada and repainted to resemble the Classic Greens.
"What happened is you've got rifles that look identical but are made on different receivers," he said in a phone interview. The receiver is the upper part of the firearm where the bolt goes in.
When one showed up in his shop, he complained to the RCMP. The RCMP began an investigation and concluded the guns may be convertible to automatic weapons, which are illegal in Canada, although Cox said that is not an issue.
He can't understand why the RCMP didn't just ban the modified repainted guns rather than the whole class of Swiss Arms rifles.
"The RCMP don't like these guns," he said. Asked why, he replied, "Because it's a military-style firearm."
Compensation being studied
James said the issue of compensation is being studied.
"I would like to let all Canadians know that all options are on the table to ensure that no firearms owner who acted in good faith suffers any consequences as a result of this terrible situation," she said.
The firearms association said the ban is part of a quiet RCMP effort to prohibit firearms in Canada.
"Access to Information records show that RCMP have an aggressive firearms reclassification agenda and that prohibitions will not stop with the Swiss Arms series rifles," the association said on its website.
Its Facebook page is even more direct with this posting: "Has RCMP Commissioner Bob Paulson declared war on law-abiding firearm owners?"
The association said the Swiss Arms rifles have been around for years without incident and some of them were even formally listed in the gun registry before the RCMP decided on prohibition.
Government blames bureaucrats
The RCMP has not given an explanation for the decision, and did not reply to emails from CBC News requesting a comment.
The gun association calls the gun ban an assault on the rights and private property of law-abiding gun owners. It's urging people to contact the government and write their MPs to get the decision overturned.
On the Conservative Party's website Friday, Public Safety Minister Steven Blaney posted a message under the heading "Unacceptable."
Identifying himself as the MP for the Quebec riding of Levis-Bellechasse, and not as a cabinet minister, Blaney wrote: "The actions of these bureaucrats are absolutely unacceptable and I will be announcing concrete measures in the coming days."
He continued, "Our Conservative government is on your side — and we will always stand up for the rights of law-abiding firearms owners."