For my CCW, I just have a box of ammunition (I chose SPEER SB +P Gold Dot) and a full mag-chamber. I plan to shoot the carry ammo up every 3 months or so, although FMJ will be fired often. I figure if I ever shoot that ammo out of it (I have fired 100+ rounds to verify that it likes Gold Dot SB +Pwell enough, at $1 a pop, I'm comfortable with that.) it will end up in an evidence locker, anyway. I just buy FMJ as I need it.
With 5.56, I have 2 ammo cans full of 64gr Gold Dot .223. I favor SBR's, and this round is tailor made for them in every way, it seems. That equates to a little over 900 rounds of it, plus a few mags full that isn't "in deep storage". These are to last as long as I live. After sighting in and occasional verification of zero, they are for flesh and blood only, against things like deer, etc. Again, at $1 a pop, I don't plan on wasting them.
I have around 1500 rounds of MK318 SOST that I use for range ammo/home-defense/whatever I need them for.
The rest is just FMJ that I order when I need it. Currently that means 2000 rounds that I ordered for a class I am taking in a few weeks. I will burn through that in about 3 days and need more again for something else, I am sure.
Shotgun ammo, I have a few hundred rounds of Ranger buckshot for my M1014.