A federal appeals court has blocked, at least partially, a brazen effort by President Joe Biden's administration to effectively ban a popular firearm style and criminalize overnight potentially tens of millions of American citizens, the Washington Examiner reported.

The court issued a limited injunction to prevent enforcement of a final rule from the Bureau of Alcohol, Tobacco, Firearms, and Explosives that seeks to strictly regulate AR-style pistols equipped with stabilizing braces by redefining them as "short-barreled rifles" under the National Firearms Act of 1934.

That rule, which was finalized in January and goes into effect on June 1, demands that owners of such weapons must register them with the ATF as regulated NFA items, replace the barrel with one longer than 16 inches, remove and dispose of or destroy the brace, turn the weapon in to law enforcement, or destroy the entire weapon altogether.

Preliminary injunction ordered, case fast-tracked to oral arguments

When the ATF published the final rule in January, it was immediately challenged with several separate lawsuits filed by numerous individual gun owners, gun manufacturers, and gun rights advocacy groups, and one of those cases -- Mock v. Garland -- was just addressed by a three-judge panel of the Fifth Circuit Court of Appeals.

On appeal by the plaintiffs following an unfavorable ruling from a district court in Texas, the Fifth Circuit panel ruled on Tuesday that "IT IS ORDERED that the appeal is EXPEDITED to the next available Oral Argument Calendar."

The ruling added, "IT IS FURTHER ORDERED that Appellants’ Opposed Motion For a Preliminary Injunction Pending Appeal is GRANTED as to the Plaintiffs in this case."

What that means is that the case has been fast-tracked to a hearing on the merits of the issue and the ATF is barred from enforcing the new rule -- at least with regard to the plaintiffs in the case, which includes two individuals, a firearms manufacturing company, and a gun rights organization known as the Firearms Policy Coalition.

A "huge victory" against the ATF

"We are very excited and encouraged by the Fifth Circuit's decision this morning," the senior attorney for constitutional litigation at FPC, Cody Wisniewski, said in a statement.

"We intend to ask the Court for additional information about who is covered under the injunction, but cannot stress enough just how important this decision is," he added. "The fight is far from over, but this is a huge victory in the battle against the ATF's unconstitutional and unlawful brace rule!"

The FPC had launched the lawsuit against the ATF's new rule that reclassified "braced pistols" -- which the agency had deemed to be perfectly legal for the past decade -- as instead being "short-barreled rifles," or rifles with a barrel less than 16 inches in length, which have been highly regulated since 1934.

The pro-Second Amendment group noted that the rule, which was created solely by the ATF at President Biden's urging without any explicit authorization from Congress, "would transform millions of peaceable people into felons overnight simply for owning a firearm that has been lawful to own for a decade, unless they either destroy their constitutionally protected property or comply with the NFA’s onerous and unconstitutional requirements."

The FPC further argued in the lawsuit that the rule violated the U.S. Constitution, particularly the Second and Fourth Amendments, as well as the Administrative Procedure Act, and was a blatant infringement upon the rights of the American people.

Motion filed for clarification of court's order

According to the FPC, the case appears to have been scheduled for oral arguments in an "en banc" hearing, meaning the entire court, at the Fifth Circuit in New Orleans, Louisiana, on June 29.

Given that the date for hearing comes nearly a month after the ATF's rule will have presumptively gone into effect on June 1, the organization has filed a motion seeking clarity from the court as to whether the injunction against enforcement applies only to the plaintiffs or is more broadly applicable, whether within just the Fifth Circuit's jurisdiction or nationwide.