Here is an extremely easy way to break into the Military base with NO Wanted Level in Grand Theft Auto Online, the multiplayer portion of Grand Theft Auto V.
This guide shows you how to break into the military base with no wanted level on GTA: Online! Steal any military vehicle. From the Rhino Tank, Aircraft the Cargobob, whatever you fancy.
No police, no military personnel to get in your way on GTA: Online when breaking into the military base. This video contains both gameplay and commentary to provide you with a step-by-step guide in how to do so.