Gun rights advocates filed a second lawsuit Friday against Maryland's strict new gun law, arguing that the state will not be able to implement new handgun requirements quickly enough to honor citizens's right to bear arms.

The suit points to the current backlog in handgun purchase applications under the existing system in arguing that a 30-day limit on time to process the new applications might not be met.

Gun rights advocates had said Thursday that they had filed a federal lawsuit to block Maryland's new gun control laws from going into effect next week, arguing that restrictions on assault weapons and large magazines infringe on their constitutional rights.

The gun rights advocates, who include individual citizens, organizations and gun shops, say the Second Amendment and case law make it clear that they are legally allowed to own military-style assault rifles and magazines that hold more than 10 rounds.

In their lawsuit in U.S. District Court in Maryland, which the office of Gov. Martin O'Malley confirmed was filed Thursday, they say the state's new gun laws would not reduce crime but would make innocent people less able to defend themselves.

Lawyers for the plaintiffs asked a judge Friday for a restraining order to stop the law from taking effect on Tuesday.

On Friday afternoon, the judge scheduled a hearing on the restraining order for Tuesday morning. The state has until Monday to file a response.

A spokeswoman for O'Malley said she expects the law to withstand the challenge.

"The vast majority of Marylanders support these common-sense efforts to reduce gun violence," spokeswoman Samantha Kappalman said. "The new law will take effect on Tuesday, and it will make families safer."

A spokesman for the Associated Gun Clubs of Baltimore Inc., one of the plaintiffs, said the new laws would keep honest citizens from being able to "choose effective firearms for defense in the home."

"Together we are drawing a line in the sand where Maryland's gun control agenda tramples the fundamental individual right to defend oneself and family in the home," spokesman John H. Josselyn said in a statement. Reached by telephone, he declined to comment further.

The lawsuit does not contest a major provision in the new gun law that calls for fingerprinting and licensing of handgun owners, a section praised by gun-control advocates as the most effect way to reduce gun violence.

"It's wonderful that they don't challenge the gun licensing" and gun dealer regulations, said Vincent DeMarco, president of the Marylanders for the Prevention of Gun Violence, calling those provisions "important, life-saving parts of this law. This is great that they're going to effect on Tuesday."

The other plaintiffs are Shawn Tardy, Andrew Turner, Matthew Godwin, Wink's Sporting Goods Inc., the Maryland Licensed Firearms Dealers Association, Maryland Shall Issue Inc., the Maryland State Rifle and Pistol Association and the National Shooting Sports Foundation.

The National Rifle Association is not a party to the lawsuit. But spokeswoman Shannon Alford said, "We are supporting it in every way we can."

Maryland's new law would ban the sale of 45 types of assault-style rifles and their copycats, limit magazines to 10 bullets, and require fingerprints and a license to buy a handgun.

The legislation is among the toughest passed by any state since the December shooting of 27 at Sandy Hook Elementary School in Newtown, Conn.

Debate over the legislation drew thousands of gun rights supporters to Annapolis earlier this year. The law passed largely with the support of urban Democrats.

Gun-rights advocates announced in April they would not petition the law to referendum, instead putting resources behind a legal challenge.

In April, then-NRA President David Keene vowed to fight the law in court, arguing that Supreme Court rulings made it clear it is unconstitutional to ban firearms in common use.