Firearms retailers estimate women made up 20 percent of their sales in 2013 (the most recent numbers available), up from 15 percent in 2010.
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Women who own guns are also often big spenders, according to the NSSF. The average female gun owner spends $870 annually on firearm purchases and another $405 on accessories, such as sights, targets and gun cleaning products, the group says.
"The women's market is a force in our industry, and manufacturers, retailers and shooting ranges are making changes to their products and services to satisfy women's tastes and needs," said Jim Curcuruto, NSSF's director of industry research and analysis, in a statement.
For gun manufacturers, the female market represents a new marketing challenge—specifically, finding exactly how to appeal to these customers.
"A lot of women struggle with the way a firearm feels in their hands," said Angelina Giudice, a marketing professional for Smith & Wesson. "It's not about the kick. It's not about the color. It's not about being pink or bedazzled. It's about how it feels."
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Women are the fastest growing market for Smith & Wesson, said Giudice. She noted that ten years ago the ratio of men to women customers was seven-to-one, and that today the ratio "has drastically shifted," but declined to cite specific figures.