Gun-owner groups on Monday filed a federal lawsuit challenging California's new law banning the sale of firearms to people under the age of 21, arguing those 18 and over are adults with legal rights to possess pistols and rifles.

The lawsuit was filed in San Diego by groups including the Calguns Foundation and Firearms Policy Coalition, and targets state laws including one that took effect in January that raised the legal limit for buying long guns from 18 to 21. The suit also challenges a previous law barring sales of handguns to those under 21.

“Once individuals turn eighteen, they are adults in the eyes of the law,” said John W. Dillon, the Carlsbad attorney representing the gun groups. “Law-abiding adults are entitled to fully exercise all of their fundamental rights, including their Second Amendment right to keep and bear arms for all lawful purposes, not just hunting or sport.”

State Sen. Anthony Portantino (D-La Cañada Flintridge) introduced the law on long-guns last year after a 19-year-old gunman armed with a semiautomatic rifle killed 17 people at a Parkland, Fla. high school in February of that year. The senator was not immediately available to comment on the lawsuit, but said last year that the higher age for purchasing guns was necessary.

“Like most Americans, I was horrified by recent events in Florida,” Portantino said when he introduced the bill. “As a father of a high school sophomore I can’t stop thinking about the unnecessary nightmare that this tragedy caused for the affected families. I feel it is imperative that California leads when Washington refuses to act.” The lawsuit, also filed on behalf of individual gun owners, argues that adults who are not convicted felons or mentally ill should have access to the full scope of the Second Amendment.

“The Second Amendment is not a second-class right and adults over the age of eighteen but under twenty-one are not second-class people,” Brandon Combs, president of the Firearms Policy Coalition. The lawsuit was filed on the same day that another controversial gun law took effect, requiring background checks for everyone buying ammunition in California to make sure they are not convicted felons.

The state Department of Justice, which conducts the background checks, said the first day went smoothly, but an attorney for gun owners disagreed. “On day one of the new ammunition background check system the problems are worse than even we anticipated,” said Chuck Michel, whose office filed a lawsuit earlier this year challenging the law. “The process takes about a half hour per customer instead of the promised 2 minutes.” He said some customers were turned away Monday because they lack some papers proving their residency in addition to a California-issued driver’s license.

“We are collecting and will be presenting these facts, and the related constitutional issues, to the court and asking for an injunction to block this useless infringement of law abiding gun owners’ rights,” said Michel. The Firearms Policy Coalition tweeted Monday it had established a hotline for gun owners to report denial of access to ammo under the new law.

CALIFORNIANS: If you experience a denial of access to ammo & your #2A rights, please inform our Legal Action Hotline immediately at https://t.co/uYphMHKAu9 or 855-252-4510 (24/7/365).
— Firearms Policy Coalition (@gunpolicy) July 1, 2019