depends on how anti-gun she is. my gf says she doesn't want to own a gun, but she sees that i enjoy it and it doesn't bother her. works just fine for us. i can go shoot holes in paper while she gets apple-flavored martinis with her girlfriends.
the real friction comes when two people have fundamentally different views about how the world works. that is how "we agree to disagree" when you're dating becomes "irreconcilable differences" when you divorce. i could not be with anyone who truly believed that guns were evil.
i once tried to date a vegetarian. i told myself "whatever, she can eat what she wants, it's not my business". it was fine for a while. but as we got closer, the fundamental difference of opinion became problematic. it did not end well.