I hate to tell you that nothing had happened at the time to make the public all of a sudden buy everything on the shelf, 22 ammo was first and then the hand gun stuff disappeared. Also this was when Homeland Security bought the millions and millions of rounds of ammo. I forget the number but look it up. That was the statement that everyone wanted to use but that is not what happened. Some thing has to happen for the public to do that and there was nothing and no kind of scare either. Just one day and all of the 22 ammo was gone. Now after a couple of months of that happening the public WAS buying everything that could be found and only in the past 2 years have you been able to pretty much buy what you want.
During the 22cal shortage I spoke to someone in the industry and they gave a pretty simple explanation. He said the there were no facilities that only make 22 ammo. A production line is shut down and retooled for 22 for a short production run each year. The demand for other caliber rounds and the fact that they make more money in those calibers derailed the change over to making 22. It became a shortage because they didn't replenish the stock.