I would hang up on that call and I don't even own a gun. Surely some people will answer, but wide swaths of the American public, gun owning or otherwise, would refuse to answer these sort of questions on basic principle and/or common sense. If you could get an estimate for what portion of gun owners relative to non-owners would refuse to answer those questions then you might have something for the statisticians to work with, but I don't see how you could estimate even that.
Surveys give you data, but sometimes that data is worth less than dirt.