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A restricted gun licence holder is seen with an AR-15 at his home in Langley, B.C. on May 1, 2020. The Tomahawk PA-22 seems to have been banned as well because it shares rear sights with the AR-15.

JONATHAN HAYWARD/The Canadian Press

Gun-shop owners are reeling from the slow-motion rollout of Ottawa’s ban on assault-style rifles, a measure that has led to the prohibition of far more models than the government had estimated, including dozens that don’t appear to fit the description of assault weapons.

When he announced the ban on May 1, Prime Minister Justin Trudeau said it would affect 1,500 models.

But one month in, the RCMP has added prohibition designations to 1,924 firearm models, according to Armalytics, a pro-firearm website that tracks changes to the Firearms Reference Table (FRT), the RCMP’s database of all known gun models and their legal status in Canada. More firearms are being added every week without any public notice as the RCMP interprets the ban’s language and how it applies to the roughly 100,000 firearms models listed in the FRT.

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The discrepancy stems from how the force is interpreting some ambiguous language in the ban.

When the government imposed the new ban through an order-in-council, it named hundreds of specific rifle models. But the order also calls for a ban on all “variants or modified versions” of the named guns.

The problem is that the term “variant” has never been defined legally in a firearms context. The job of interpreting it has been left to the RCMP, who have labelled dozens more models as prohibited, baffling gun vendors.

Take the Mossberg 715T Tactical 22, for instance. From a distance, it looks exactly like the kind of modern rifle the Liberals intended to bar. But the exterior is a plastic shell. Inside are the guts of a run-of-the-mill .22 rifle, a light calibre that is largely nonrestricted in Canada.

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The FRT indicates that the gun has been banned as a variant of the AR-15. But calling the Mossberg an AR-15 is like saying Paris Las Vegas is the same as Paris, France.

“We continue to work with the RCMP to ensure that the public Firearms Reference Table is updated as quickly and as thoroughly as possible to reflect changes that were brought in that day,” said Mary-Liz Power, press secretary to Public Safety Minister Bill Blair. “Our government is considering options to bring forward a classification system that will be constantly renewed to ensure clarity for the public, law enforcement and manufacturers alike.”

The RCMP has yet to answer technical questions about the FRT updates sent last week.

The lag between the May 1 order-in-council and the RCMP’s ongoing interpretation of the regulation means some sales have become illegal retroactively.

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The Mossberg 715T Tactical 22 wasn’t on the RCMP’s banned list until May 20. But Ellwood Epps Sporting Goods in Orillia, Ont., had sold two of the rifles the previous day.

“Those were guns I ordered from my vendor and then sold after May 1,” said Wes Winkel, the store’s owner. “By law, those guns are supposed to be brought back and then I’m supposed to send them back to my vendor because I’m not supposed to have them either.”

Mr. Winkel, who’s also president of the Canadian Sporting Arms and Ammunition Association, said he has contacted the RCMP about how to proceed, but has yet to receive an answer. “To say this has been an epic disaster would be minimizing things,” he said.

Matthew Hipwell, owner of Wolverine Supplies in Virden, Man., has had much the same experience. The store has long imported a nonrestricted semi-automatic 12-gauge shotgun called the Alpharms SA-15. The firearm was not named in the order in council, and Mr. Hipwell thought he was in the clear to continue selling it. But on May 17, he checked with the RCMP and found out it had been added to the ban.

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“They continue to change the FRT behind closed doors,” he said. “This has left people all over the country second-guessing about whether a firearm is prohibited or not. And there has been zero communication.”

The implementation of the ban has made for some unlikely allies. A.J. Somerset, author of Arms: The Culture and Credo of the Gun and a proponent of what he calls “reasonable and effective gun control,” has been one of the foremost critics of the RCMP’s recent firearms decisions. A former Canadian Forces gunnery instructor, he has taken to Twitter to explain in technical detail why some of the new prohibitions don’t make sense.

One shotgun he profiled, the Tomahawk PA-22, seems to have been banned because it shares rear sights with the AR-15.

“It seems that what’s happening is the RCMP is basically going through the FRT and banning firearms with any reference to the AR-15,” he said. “We’re seeing guns that actually bear no design similarities to the AR-15, except superficially, being banned.”

The FRT is not a legally binding document, but it does inform and advise law enforcement in laying charges. Any challenges to the database would need to be made in court.

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“This makes no sense,” Mr. Somerset added. “I’m convinced this would never stand in court.”

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