I read an article a while back which basically said
Stock comes and goes, stores usually order several weeks/months in advance to receive shipment, they have a finite stock and usually stock items so they get sold as soon as it can come in. They keep a balance, and factories for guns and ammo can only pump out as much as their weakest link... if the factories can double up production, but their raw material supplier can only boost up 5%.. 5% more is all you get. There was a short term demand which was retarded and unheard of, people bought up stocks and backordered numerous items, so instead of a years sales evening out, we have it all in the span of a few months, the orders which normally trickled in are now all accounted for, dealers placed additional orders (all of them) and get placed into the queue, as the items come out (maybe 1000s at a time, who knows) they get sent to the backorders, creating this perception of no supply when they are supplying tons of it to the people who ordered a hoarders amount of items. Eventually it'll go back to normal levels/prices (maybe even less as demand drops sharply once the outstandings are filled).
Take it for whats it's worth.