How can you block nails, and bottle caps along with other peices of trash. I was hunting in all metal mode yesterday, and found a bunch of old items. Nails, bottle caps, wire, pennys, bullets, fishing wieghts, and small metal beeds. I found no gold but was wondering how to block some of the unwanted targets. And what is the expectencey range of the GB Se on a peice of gold the size of a grain of rice? Just want a ball park figure if you would please. Well tku for the feed back.