Like I mentioned before, they have to rotate the duty ammo they carry on a daily basis and dispose of it so there isn't usually that much of a "stockpile." Our armory had enough for the entire dept to have three full mags (pistol) plus about half that as reserve. The ammo that was rotated out for disposal was either shot by the RSOs during instructor training, shot by neighboring commands as "fam fire", or used to get marginal shooters a little more practice than the allocated rounds. Our allotted shoots were 150 rounds but we usually let everybody shoot an extra 100 before we officiallt started to shoot to keep our expenditures balanced. That extra was the duty ammo that was about to be expired.