Don't Fear The Clear
Get thee to a gun store or on the internet and find out what it takes to get "medically cleared" to own a gun or rifle in your state (let's forget about bazookas and RPG's).
There are different criteria for different situations (e.g. fire fighter, police, schizophrenic, mass murderer,etc). Then see if you can get a doctor to sign-off on them. That's the only legal way to do that, as far as I know.