How to get parents to allow me to get a gun?

For years I have wanted a gun. I am 16 years old and very responsible. I always obey my parents and never give them any back-talk. they have allowed me to get bb guns, paintball guns, and airsoft guns, but however I think that if i mention a real gun they would go insane. I don't want a huge caliber gun, just like a .22 to start. I would also like a shotgun for bird hunting and shooting stuff. I feel like I have no idea how to ask because my dad is against guns as it is and he thinks that no matter what they are not necessary. this is because he is a doctor and has seen some gory stuff in the hospital, and he always thinks I will hurt myself, but i am very responsible. I would also mention getting a hunting license and attending gun safety courses and hunting courses. any suggestions on how i should approach the issue? is it unusual that I have an interest in guns?