I don't believe I have ever been accused of being a conspiracy theorist. However as the old saying goes, just because you are paranoid doesn't mean they are not actually out to get you.
I think the enormous quantities of small arms ammunition along with the governments priority status has in large part helped fuel this shortage.
http://www.infowars.com/dhs-to-buy-3...nt-ammunition/
http://offgridsurvival.com/ammoshort...fthingstocome/