DALLAS (AP) — A federal judge has struck down one of Texas' few remaining firearm restrictions, finding a law that barred adults under the age of 21 from carrying a handgun was unconstitutional. U.S. District Judge Mark Pittman in Fort Worth on Thursday ruled that the state law prohibiting most 18- to 20-year-olds from carrying a handgun outside the home violates the Second Amendment right to bear arms and cannot be enforced. He stayed the ruling from taking effect for 30 days.