(CBS News) SAN FRANCISCO - Former Sen. Phil Gramm of Texas once said, "I own more shotguns than I need, but not as many as I want."
A lot of gun owners feel that way, but we wondered why so many owned the same kind of assault rifle used in the Newtown massacre last week.
Gene Hoffman says he owns four AR-15s for hobby and sport. The internet entrepreneur has 11 other guns in his home south of San Francisco.
"If you ask a golfer why he needs 15 clubs instead of 7 he'll tell you, well, with certain shots, I like to use that other putter," Hoffman said.
"Look, the right to firearms, the civil right to firearms, is dangerous and that's why it's a right. This isn't something that's free or easy. There will always be people who disagree with it." he added.
The AR-15 is often called the "Barbie doll" rifle because it has so many accessories.
"You can buy one and buy a lot of different parts for it. You can hunt with it, you can target shoot with it," Hoffman said.
A 2011 survey by the Shooting Sports Foundation found 49.1 percent of gun owners who bought that gun did so for target shooting; 22.8 percent bought id for hunting; and 28.1 percent for protection.
More than 3 million Americans now own an AR-15.
"The AR-15 is the kind of mainline rifle these days. It's the most popular selling firearm. It's kind of like talking about a Chevrolet," Hoffman said.
These weapons have become stars of cable TV shows and popular video games. Gun makers market them mostly to men. Overall production of military-style weapons and rifles increased 75 percent in eight years, from 2001-2009.
Hoffman said that he does believe in some gun control.
"There are a lot of things we can do to make sure only the right people have firearms, and if a mental health professional decides they are dangerous they'll lose their gun rights for 10 years or life," he said.
Hoffman plans to add two more guns to his collection bringing his total to 17.