Depends on how much you shoot. I keep 150 rounds of factory +P+ JHP in 9MM. That is carry/SD/HD/ SHTF ammo.
I try to keep at least 4000-5000 rounds of 9mm FMJ for practice.
5.56, I have 300 rounds of LC M855 Ball in magazines. Several thousand reloads and cheap M193 ball for practice.
I don't shoot my .303s very much, so 500-600 is adequate.
I didn't fight to defend your freedom so you could vote to take away mine.
"A man who has nothing for which he is willing to fight, nothing which is more important than his own personal safety, is a miserable creature and has no chance of being free unless made and kept so by the exertions of better men than himself.
John Stuart Mill."