AUSTIN (KXAN) — On Monday, activist and owner of Central Texas Gun Works, Michael Cargill, announced he will file a lawsuit against the local Bureau of Alcohol Tobacco and Firearms’ Bump Stock Ban — where he will surrender his bump stocks later in the afternoon.

While Congress has banned “machine guns,” it has not banned bump stocks — a device that when installed allows a semi-automatic to fire at a rapid rate, much like a fully automatic gun.

A Central Texas Gun Works release from Cargill states:

“For years, the ATF said that bump stocks were not machine guns under the law. Now it is saying the opposite, which means that hundreds of thousands of law-abiding Americans who relied on the ATF’s approval of bump stocks are suddenly felons. That’s not how the law in America should work.”

The New Civil Liberties Union, a nonprofit civil rights organization that is representing Cargill in the case, has explained the scope of the lawsuit is not about whether or not bump stocks should be outlawed, but rather, which governmental body should be changing the law. The NCLA believes the ATF’s ban was unlawful.

The Gun Works release ends by saying: “Congress — and only Congress — can convert lawful activity into unlawful activity. But Congress has not banned bump stocks, so the ATF’s rule violates the Constitution.”

Cargill will reportedly announce the lawsuit on Monday afternoon when he surrenders his bump stock devices at the Austin ATF Field Office.