In the state of Tennessee, it is illegal to shoot/discharge a projectile within a municipality.
http://en.wikipedia.org/wiki/Legal_issues_in_airsoft#United_States go there and it says most of the requirements
Although there are no enforced federal laws regarding the sport of airsoft (beyond shipping restrictions of certain models and makes), most laws reside on either your state, local, or community...
Legal, but needs to have orange tip on the end of barrel.
Google it or ask some of the higher ups in the city council.
You can play air soft I would do it a lot before I moved