Barely a week after taking effect, a state preemption law that makes it easier for gun-rights groups to challenge illegal local firearms measures in court is already effecting change: Nearly two dozen Pennsylvania municipalities have decided to scrap their “potentially problematic” (i.e., illegal) ordinances rather than face litigation.

Four pro-gun groups and several residents put nearly 100 Pennsylvania municipalities on notice that they would face legal action unless they rescinded their firearms laws.

At least 22 of those municipalities have reportedly already repealed them, or indicated they planned to do so. This means dozens of towns know their laws are illegal, just like hundreds or thousands of municipalities across the nation.

Pennsylvania’s capital is one of the obstinate ones and is facing a lawsuit believed to be the first filed under the new law. The lawsuit filed Tuesday in Dauphin County court named as defendants the city of Harrisburg and various city officials, who will have to answer allegations that various firearms ordinances violate the state’s preemption law that prohibits local governments from enacting gun control ordinances.

The NRA, on behalf of its 5 million members across the country, has also filed lawsuits against the cities of Pittsburgh, Philadelphia, and Lancaster, which have openly defied state law for decades.

Meanwhile, PA state Rep. Thaddeus Kirkland (D) says he will soon introduce legislation to prohibit the use of targets that depict human silhouettes at shooting ranges across the Commonwealth (with an “only ones” exception, of course). Apparently full 3-D human-shaped targets would still be legal.