The majority of states have no waiting periods for handguns, or long guns.
Despite all the hype about Florida being the "WILD WEST" after the TM incident, we are one of the few states with a waiting period for handgun purchases without a CWP.
Only eleven of the fifty states, have any waiting periods at all for long and/or handguns:
http://smartgunlaws.org/waiting-periods-policy-summary/
Depends on where you live, and your state AND local laws.