A spike in gun sales is common after a mass shooting, but the Connecticut tragedy has generated record sales in many states. Colorado set a single-day record for gun background check requests the day after the Connecticut mass shootings, and some online retailers are removing assault rifles from websites in part because of diminishing supplies.

Nevada saw more requests for background checks in the days after the shooting than any other weekend this year. Some gun shop owners are even holding back on sales, anticipating only more interest and value after President Barack Obama on Wednesday tasked his administration with creating concrete proposals to reduce gun violence.

Robert Akers, a Rapid City, S.D., gun seller specializing in assault-style rifles, said he has about 50 of the weapons in stock but he’s not actively trying to sell them and has even turned off his phone.

“It’s a madhouse,” said Akers, owner of Rapid Fire Firearms. “Any time they have one of these shootings or an election, it gets that way. I don’t even want to sell them right now because I won’t be able to replace them for probably six months. … The price is only going to go up higher.”

At least three companies that make armored backpacks designed to shield children caught in a shootings also are reporting a large spike in sales and interest.

The body armor inserts fit into the back panel of a child’s backpack, and they sell for about $150 to $300, depending on the company.

The armor is designed to stop bullets from handguns, not assault rifles like the one used by the Connecticut shooter. The manufacturers and some parents say that while they don’t guarantee children won’t be killed, they could still be used as shields.

“Just like a seatbelt increases your odds of surviving in a car crash, these increase your odds of surviving being shot,” said Kerry Clark, president of Texas-based Backpackshield.com.

Ken Larson, 41, of Denver, Colo., already had an armored backpack for himself and convinced his wife to buy one for their 1-year-old after the Connecticut shooting on Friday, when a gunman stormed Sandy Hook Elementary in Newtown and massacred 20 first-graders and six adults.

“It’s a no brainer. My son’s life is invaluable,” Larson said. “If I can get him a backpack for $200 that makes him safer, I don’t even have to think about that. Where is my credit card?”

Though Larson knows the backpack won’t guarantee his son’s safety when he starts school, he says it’s a worthy precaution.

“Kids already carry backpacks. When there is a shooting, you run for your life,” he said. “Having it right there and on when he runs for his life gives him more safety.”

Elmar Uy, vice president of operations at Bullet Blocker, a Massachusetts-based company that has sold the backpack armor since 2007, says the company’s sales have tripled since last week.

At Amendment II in Salt Lake City, sales of children’s backpacks and armored inserts are up 300 percent.

“The incident last week highlights the need to protect our children,” said co-owner Derek Williams. “We didn’t get in this business to do this. But the fact that is that our armor can help children just as it can help soldiers.”

Amendment II was founded about two years ago using a new lightweight nanotechnology to make body armor products for soldiers and law enforcement less cumbersome. They began making the backpack inserts about six months ago, and also sell child-sized bulletproof vests. While the backpack sales still represent a minor part of the business, they now sell two varieties online — one featuring Disney princesses and the other a scene from the movie Avengers.

Clark, president of Backpackshield.com, began making youth backpacks after the mass shooting at Virginia Tech in 2007.

“I don’t do it for the money, but to save the lives of kids,” Clark said. “We’ve got to do something more than just hide in the corner of the classroom.”