I use mesh tarps. One or two. They are black and show the brass easily. Mine are 14'x20' from Harbor freight. They have small holes (think door screen) and the wind doesn't mess with them too much. On very windy days, I weigh the corners down with something...anything. Depending on how far the cases fly (Sigs really toss 'em!), I adjust my position next to them. When done, fold and collect the brass in the center. Scoop out! Easy peasy!

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Thugs that comply don’t die!