Most multi-marts will have a sporting goods dep't with fishing gear, including minnow/fish nets. Get a big one [12 inch or so] and fabricate a stand to hold it right next to your Luger while you fire. You may need to make spreaders out of straws to hold it open enough to actually catch the brass.
Mine sits on the bench. The base is an old Xmas tree stand with folding legs. The fish net is screwed to the stand.
Works great.
