I've been talking to a buddy about going in together on huge quantities of brass recently. We found a few ranges that strictly do not allow shooters to reclaim their brass. Once it's fired it goes to the range and they sell it. Normally they sell it for whatever scrap value is but we've been talking to them about a deal for buying a large quantity. I found out yesterday that they've done this before for people. I don't know how much they have but they seemed confident they could fill an order for us for almost 1000 pounds of brass.
I've never bought anything on this scale before or dealt with an auction before. The way the ranges sounded we talked to said our request wasn't uncommon. So maybe try a range if your looking for a large quantity. Hopefully it works out for me and my buddy.