I'd say the scarcity of 40 SW, at least in part, loops back to the big manufacturers changing those machines over to other calibers due to low demand (LEO and civ). While folks may have been buying up cheap 40SW, the facts seem to be that they weren't taking them to the range (still cheaper to shoot 9mm if you wanted to get some range/plinking time in). And since 40SW ammo is likely bit of a "dog" for gun stores to stock (low margin, higher cost, and weak turns), they're hesitant to put inventory dollars into the caliber (safer to stick with 9mm/45ACP/223/556). That said, while there may be some localized demand for 40 SW while the manufacturers catch up, I'd say it'll come back pretty quick.