Its not worth your life
I am not military, but I can honestly say that I would never attempt to seek shelter at a military installation of any kind. There are several reasons for this. 1 it would be crowded with every other desperate individual, and probably many infected or already turned people. 2 the military will not just let everyone onto the base. 3 they do not hand out guns to everyone who shows up either. 4 they may even have orders to fire on any crowd, to eliminate the infected! the military would be more worried about being over run than saving every civilian. 5 many of the military personnel would surely have abandoned their posts to protect their own loved ones, so they would be even further weakened in numbers/ "protection". 6 even if a military base were abandoned, you would not be able to "break" into any arms rooms. They keep them locked down tighter than fort knox, and sometimes keep the ammo seperated from the weaponry. 7 not to mention all the commotion going on at the base would attract more undead, if they were not already present.
For these reasons and more, I would stay FAR AWAY from any military installation/ operation. They risks outweigh any possible benefits, unless ofcourse you are already a high ranking military official (with access to weapons/ heavily secured military structures).
My plan also includes avoiding stores of any kind for many of the same reasons. Unless you are the first one there, and can get in and out quickly and easily with adequate supplies to obviate the risk, I would avoid it altogether, atleast until the shit has hit the fan, splattered the wall, and begun to slide down. In other words, have an adequate amount of supplies stored to last until the worst part of the outbreak is over, when there are fewer screams and gunshots outside. you want to avoid the beggining of the outbreak at all costs, because that is panic time and every survivor is as much a threat as the undead.
Once things have died down a bit, if you are still alive and havent been irradicated by military counter measures, (or ofcourse zombies) by all means form a raiding party and search for supplies. Food, water, weapons, ammo, and household supplies. Horde them. Get as much as you can. Search locations closest to you and work your way out. your neighbors house may not be wal mart, but wal mart may be picked clean or crawling with the undead, or down 20 miles of gridlocked cars, walking corpses, or vicious gun fights. Number one rule= SAFETY. When in doubt, dont F-ing go out!!!!