[Legbreaker]

Z Nation is another show where they seem perpetually out, or close to out of ammo. It's quiet common for them to have to pool their resources and find they've got three bullets, two paper clips and a winning smile left and little else. Mind you the show proper starts about three years after Z day. Food is often also in critically short supply with one episode almost seeing them die of starvation and thirst.

I can't speak much about overall stocks, but I know my original reserve infantry battalion (Australian) was allocated something like 10,000 rounds of 7.62N ball, about the same 7.62N belted, and an unknown amount of 5.56N (we didn't even have any weapons to fire it until the regular army switched to the F88 and their M16s got handed down), and 9mmP (for a total of 7 pistols in the entire battalion).
This was the annual training supply and could have been a bit less (20+ years ago). It was rumoured that although we were usually a bit short on rifle and machinegun ammo, the battalion had enough 9mm left over to last about a dozen lifetimes! I think we were still being allocated 9mm for the old F1 SMGs we'd handed in a few years before, so it just kept piling up.