You estimate is far too low as well as frequency. Let's just take DHS for example as they have the specific contract (but it isn't stated if that contract extends to other agencies like the DOD).
Just the 'armed' departments under DHS include: FBI, US Marshall Service, ICE, Federal Air Marshall Service, Secret Service, Layered Nuclear Defense Agency, National Fugitive Operations Service, Protective Investigation Service, Diplomat Security Service, US Coast Guard...etc.. (say close to 100K armed under this umbrella)
There also is the Federal Law Enforcement Training Center in which many State and Local law enforcement agencies receive training.
You also have to account that members of some of these agencies are practicing every week, not just a few times a year for qualification.
Then, take into account that the contract isn't a 1 lump sum 450 million rounds but simply locking in a contract up to five years for up to 450 million rounds at that price. They could buy one thousand rounds or one million rounds. It isn't a sale, just a pricing agreement.
It isn't as scary as people are making it out to be. Especially when one considers how many billions of rounds taxpayers buy for government agencies each year. (I'm sure the DOD umbrella burns through several billion alone).
They could buy one thousand rounds or one million rounds. It isn't a sale, just a pricing agreement.