In the wake of a landmark U.S. Supreme Court decision last year that significantly limits what the government can do to restrict guns, states led by Democrats have scrambled to circumvent or test the limits of the ruling. A few have approved new gun restrictions. Oregon even passed a ballot initiative to ban high-capacity ammunition magazines.

But this week, supporters of the new gun measures suffered a pair of setbacks, underscoring the rippling effect of the court’s decision.

On Tuesday, a three-judge panel of the U.S. Court of Appeals for the Fourth Circuit in Richmond, Va., ruled that a 10-year-old Maryland law related to licensing requirements for handguns was unconstitutional.

On the same day, a state judge in southeastern Oregon concluded that a ballot initiative approved by voters in 2022 that would prohibit high-capacity magazines and require background checks and training to obtain gun permits violated the State Constitution.

For the Gun Owners of America, a lobbying group in Virginia that has been active in litigation, the twin rulings merited a news alert distributed to its members, heralding “good news for gun rights supporters to celebrate this Thanksgiving!”

In an email, Erich Pratt, the group’s senior vice president, said he was “thrilled” by the ruling in Oregon and found the Maryland one “just as encouraging.”

“At the end of the day, more and more Americans are realizing the government cannot be trusted with their safety,” Mr. Pratt said, citing a new poll from NBC News showing that gun ownership had been rising to record levels.

Legal scholars were more circumspect about what the latest rulings portended, noting that other recent court decisions, such as in Illinois, and arguments in a new gun case before the Supreme Court suggested that there was still some momentum for gun violence prevention laws.

Still, they said that this week’s decisions reinforced an unmistakable trend in which judges, especially ones appointed by Republican presidents, were interpreting the Second Amendment as broadly as possible.

The aftermath of Bruen has also prompted a surge in lawsuits challenging various gun laws, according to Giffords, a gun control group, with more than 450 decisions trying to interpret the case.