There's one group of gun owners celebrating the Wal-Mart decision to stop selling pistol ammo, .223NATO, and 7.62 Russian.
It's the people who own gun stores. They've never been able to compete with Wal-Mart on price and now they have been given a gift. They'll get more sales of ammo, have more people come through their doors, and possibly sell more guns and other supplies due to the increase customer traffic.
Go visit your local version of Gun Universe and buy a box of 9mm. While you're there, look at what he's got in stock. Buy some full size magazines before the next panic, consider what fills a hole in your safe, and get to know the man behind the counter. He's been waiting for you.