Shotgun powders seem to be more available than any of the rifle or pistol powders. Especially Varget, CFE-223, or H-335 in any quantity, (8 lb. jugs). These powders are the most popular in loading .223/5.56 MM and .308.
Everybody and their brother has taken up reloading in the past year, because of the ammo shortage since Newtown. I was told by one of the biggest reloading suppliers here in Phoenix, (Bruno's Shooters Supply), it won't get any better for at least three or four more months. Even then it won't be plentiful. I haven't seen any new .300 Win. Mag. brass in over a year anywhere.
This isn't going to improve because the demand has increased PERMANENTLY because there are more people in the reloading game. Until the powder manufacturers increase their production capacity, the shortages will continue. Now, if you can find ANY of the more popular rifle powders, it's only in 1 pound containers. Primers are starting to become more available, albeit it a much higher price than just a year ago. In the mean time, if another high body count shooting happens, and it will, expect this to get even worse. As Emeril says, "That will kick it up a notch".
I've been stockpiling 9 MM, .45 ACP, and .223 / 5.56 MM for years. So now I'm in good shape. With that said I, like everyone else, is getting sick and tired of this. I'm constantly on the prowl for reloading components, and buy when I get the chance. It's becoming a real PITA out there!