Are you not aware that only criminals kill people? Also, there were 4,081 people killed in 2011 by someone who used knives, bats, hammers and other non gun objects to commit their crimes. In that same year 323 were killed by someone who used some type of rifle to commit their crimes. Don't you see that criminals are the problem and not the tools they use?
As far a the gay marriage thing, any gay man has the same rights as straight man. He can marry one woman who he chooses. The same goes for a woman who is gay, she can marry one man whom she chooses. There is no discrimination against gays where marriage is concerned.