Gun owners have until the end of the weekend to turn in, modify or destroy any firearm magazines that can hold more than 10 bullets.

The Murphy administration set a 180-day deadline to get rid of higher-capacity magazines when Gov. Phil Murphy signed a package of gun laws back in June. That deadline ends Monday.

Members of the armed forces and law enforcement departments are exempt from the new rule. But civilian violators could face up to 18 months in jail per magazine that is over the 10-round limit.

Many gun owners say that the new rule was poorly implemented.

“Overnight you’ve turned law-abiding citizens into felons,” says Rick Friedman, founder of RTSP firearms range.

Friedman says that he has a more than four-week waiting list at RTSP for gun owners who need to modify their magazines to hold 10 rounds or less. The grandfather clause that allowed gun owners to keep their higher-capacity magazines expires Dec. 10. The magazines need to be modified, destroyed or turned in.

“Please, bring your magazines in to be altered, get rid of them. Do not be in possession of a 15-round magazine,” Friedman says.

The Association of New Jersey Rifle and Pistol Clubs sued to try and get the magazine limit thrown out as unconstitutional. But the Third Circuit Court of Appeals sided with the state and upheld the law.

New Jersey Attorney General Gurbir Grewal tweeted, “A sensible law to address mass shootings. Today, the court of appeals upheld the law. Big win for public safety and law enforcement safety!"

Murphy and state Democratic leaders lauded the gun control bills at the June ceremony where the governor signed them into law.

“We passed this package of legislation, and we fought tooth and nail for what was right and what was common sense and what was rational,” Assemblyman Lou Greenwald said at the time.

Moms Demand Action for Gun Sense in America also applauded the effort, saying in a statement, "Gun safety measures such as background checks, high-capacity magazine limits and a system to empower families and law enforcement to act on red flags before they escalate into tragedies can all help save lives."

But Friedman says that he does not agree.

“It's not the 11th round that's the dangerous round. It's the person behind the firearm that we believe that poses the danger,” he says. “Not the type of firearm, not the amount of ammunition. Someone is going to do something that's illegal or criminal, they don't care about what law is passed.”

New Jersey previously set the ammunition limit to 15 rounds in 1991.

The Association of New Jersey Rifle and Pistol Clubs says they will appeal the court decision all the way to the Supreme Court if they need to.