As an agency the FBI has probably changed "official handguns" more times than any agency i know of. Back a few years ago the American Rifleman Magazine listed all of them and my head was spinning! I don't remember the exact count, but it was a LOT!

I suppose there are many reasons like female agents with smaller hands and frames. Less practice time on the Ranges these days, less instruction, more and faster ballistic advancements, dress code changes, etc all contribute to the many changes too. I would imagine Politics and who is heading up the Agency also has something to add into the mix.

The bottom line is that they don;t have the same "budget restrictions" that local LE Agencys have to contend with and they usually get the Gov't to cut the check, whereas local LE Agency's probably need more and better justification for spending more of the taxpayers hard earned money.