Ronvandyn:
Actually, I'm practicing sloppy reporting so that the major news agencies will hire me as a crime reporter and I can write articles about semi-automatic revolvers.
Yes, you are entirely on target. it wasn't the TSA that was referenced in that particular Examiner article. [Best bet would be that they also do buy a few rounds from time to time for whatever purposes.]
Many web articles say it's the SSA, HHS, and DHS. Some writers have asserted that these major purchases might be affecting the supply of cartridges to the handgun consumer market. Haven't noticed such in my shopping, however.
I guess if a federal agency is large enough and has enough offices, buildings, garages, grounds, whatever, then it will have a fairly large security staff, and many of them will be armed.
Situation is interesting. It does raise the paranoia level of those who engage in that sort of thing.
Thanks for the calibration.