I've had it happen to me on a much smaller scale, 500-1000 bullets, and I decided that much the easiest way to clean them was to melt and skim. Mine came out of a six cavity mould in something under two hours so it did not take a lot of thinking.
However, my bullet storage unit is made from 2x8s, cleated, deckscrewed and screwed to the wall. It ain't coming down unless the building does and maybe not then.