Those rascals at Greenwood and Castleton have 9mm bulk, .223 bulk, and yes .22lr bulk behind gun counters, not accessible to public. The only way to get it, is to buy a firearm from them. They have a lot of those three calibers. What else, who knows?
I was there the other day and they had a lot of .40 100rd packs on the shelf, just not sure who wants to pay .50 a round for it.
The cheapest .40 on luckygunner.com is .79 a round. So $.50 sounds pretty good.