Do the edges, take one day and just hunt all the edges and brush lines, i found a few nice 925 rings just by doing those edges. all the way around the academic field, then turn around and do the way back, hunt about 4-5ft away from the edge. another trick of mine is to go where they would dump the snow from plowing the parking lot, youd be surprised whats lost in parking lots in winter time.... just a few tips for ya, maybe youve` tried them already, maybe not.