LOS ANGELES — The bustle inside LAX Ammunition on the Friday before Father’s Day betrayed the gloom of the outside sky.

Employees inside the Los Angeles-area gun shop had their hands full chatting with customers who were looking to replenish their ammo supply before July 1, with some customers spending hundreds of dollars in the process.

Why the hurry? That’s the day a new state law will require almost all buyers to go through background checks before being able to buy bullets, potentially increasing the amount of time and money it takes to make purchases.

“We're probably up by 400% from where we were last year for this past month, and this month, in total sales,” says Daniel Kash, the store’s president.

As it is, California has some of the toughest gun laws in the nation — the state bans most assault weapons and restricts the sale and possession of large capacity magazines. There’s also a 10-day waiting period prior to the sale or transfer of a firearm, among other restrictions.

The passage of Proposition 63, a gun control measure approved, coincidentally, by 63 percent of California voters in 2016, will strengthen those laws by taking aim at the sale of ammo.

“Everybody that has a gun ... knows about the law that's upcoming,” Kash says. “That's why you see the store being as busy as it is this week for the Father's Day Sale. People are stocking up right now, basically.”

How will it work?

The new law — championed by Democratic Gov. Gavin Newsom, a longtime advocate of gun control — is meant to protect the public by keeping ammunition from getting into dangerous hands, the state says.

Here’s how:

Customers will have to receive a background check every time they make an ammunition purchase, paying $1 each time.

Those who don’t already have their information in the Department of Justice’s system for these point-of-sale screenings will have to pay up to $20 for an initial screening.

Vendors will have to make sure customers aren’t on a DOJ list that names people who are prohibited from buying guns for various reasons — for example, committing a felony — before selling to them.

All ammo sales will have to take place in person — even online orders will have to be shipped to a licensed vendor’s store before customers can pick them up.

Gun owners and enthusiasts aren’t happy, arguing that the new law will cost extra time and money.

“The biggest question on people's minds is what the process is going to be like, and how burdened someone's going to be, whether it's going to take it a tremendous amount of additional time, or whether it's going to cost them more money,” says Alexander Reyes, a manager at Martin B. Retting, a gun shop in Culver City near Los Angeles.

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Advocates, though, remain convinced that the inconvenience to law-abiding gun owners is necessary for the public good.

“This is about preventing all forms of gun violence and ensuring we're doing everything we can, through a second-long background check, to ensure that people with the most significant histories of criminal violence, or severe mental health impairments, are not able to access [guns],” says Ari Freilich, the California legislative affairs director for the Giffords Law Center to Prevent Gun Violence in San Francisco.

‘Unregulated’ ammo sales

In a 2016 op-ed in The Sacramento Bee, Newsom wrote that the new law would “treat ammunition sales as gun sales,” a measure that, paired with the others in the bill, would help “keep guns and ammo out of the wrong hands.”

“Although California has led the nation in gun safety laws, those laws still have loopholes that leave communities throughout the state vulnerable to gun violence and mass shootings,” the text of the act, drafted by Newsom, reads. “We can close these loopholes while still safeguarding the ability of law ­abiding, responsible Californians to own guns for self­-defense, hunting and recreation.”

One of those loopholes is the lack of regulations around ammunition purchases, says Amanda Wilcox, the legislation policy chair of Brady California, a state chapter of the Brady Campaign to Prevent Gun Violence.

“Prior to any of this, no one knew who was selling ammunition or buying ammunition, ammo sales were completely unregulated,” Wilcox says. “You could sell ammunition out of your trunk of your car, anywhere. It was existing law that if you're prohibited from ... purchasing and possessing a gun, you're also prohibited from purchasing ammunition, but there's no way to enforce that law.”

In other words, Wilcox says, the new measure could help prevent individuals who illegally possess guns from being able to purchase ammunition for them, while simultaneously alerting vendors and law enforcement.

“Obviously, we want people who can't pass a background check not to buy ammunition,” Wilcox says. “The legislation does that.”

‘They’re going to get it’

Some gun owners, however, insist that the new law does little to address illegal activity while unfairly targeting those who already follow the law.

“Anyone who is willing to murder innocent people does not have a regard for laws, clearly, and they are able to cross a border to purchase ammunition and violate existing California laws,” says Ryan McDonnell, a gun owner from Alameda, east of San Francisco.

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Others say the new restrictions will simply encourage gun owners to purchase ammo elsewhere, negatively impacting California vendors.

“To me, it’s just a way for the government to make more money … people are gonna go other places to get what they need,” says Kevin McGlothan of Compton. “They’re going to get it regardless, they’re just going to go a different way and cut the little man out.”

Adding to the stir is the reality that gun shops themselves aren’t sure how the new law is going to affect the in-store checkout process.

“The reality is, the California Department of Justice Bureau of Firearms has said that they're not going to unveil the system, even to us, until July 1,” Reyes says. “So even though we have a vague idea … of what the process is going to be like, we still don’t 100% know, because we're not going to have access to the system until July 1, same as everybody else.”

‘A matter of patience’

Confusion and resistance aside, Reyes hopes the new state law won’t greatly affect the average gun owner. While it's unknown how many people in California fall into that category, three in 10 adults in the United States own guns for self-defense, hunting, sport shooting or collecting, according to the Pew Research Center.

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“The average gun owner is probably not going to be as impacted as they think they're going to be,” Reyes says. “But, ultimately, I think people are going to find the inconvenience, and the hassle, and the pain to the wallet … to be the biggest thing.”

He adds, “There’s a ... lack of concrete information and hearsay and gossip and everything. But it all gets straightened out, it's just a matter of patience and dealing with it.”

Even if the new law doesn’t altogether end gun violence, supporters believe in California’s vision to provide a path for other states to follow.

“We can — and should — have a conversation about increasing our investments in mental health resources,” Freilich says. “None of that should also distract us from having a simultaneous conversation about when that person sets out wanting to do violence … It’s not an either-or.”