"That's true, but its more of a side-effect than directly The Panic itself. Those firearms being sold, even though they're selling because of The Panic, will result in "sustained demand"."
No, it's a direct effect.
Before the first panic in 2007, production of .22 ammunition in the United States had stayed roughly the same for decade or more and had barely risen since the middle 1980s. Demand and supply had reached a nice equilibrium at between 3.5-4 billion rounds a year, with total production capacity of roughly 4.5 to 5 billion rounds a year.
Even worse, firearms sales had been on a gradual cooling trend from the early 1990s to 2006.
Since 2007, that equilibrium has been thrown totally out of whack.
If ammo producers didn't think that there would be sustained increased future demand based in part on total number of new firearms entering the marketplace, they wouldn't be expanding. It's horrifically expensive to expand an ammo line. Rumors among some of my friends who are still in the business is that the "new normal" production equilibrium is going to be close to 5 to 5.5 billion rounds a year, with slated production expansion able to bump that closer to a maximum of about 6 to 6.5 billion rounds a year.
If they didn't expect sustained consumption to last, they would be telling everyone to suck it up and ride it out, that it's a temporary fluctuation that will right itself and the equilibrium will return in due time.
That happened with primers back in the early to mid 1990s.