I'll tell you how I do it..
Being in So Cal, it's sanded in right now so my strategy will probably be different than other regions .
I tend to get to the beach around 3am. Because So Cal beach water is a bit cold, only kids/teens are in the water so I do the towel lines (until later in the summer) to the top of the dry paying extra attn to entry points, staging areas, rental areas, and shower/bathroom locations. Volley ball courts are ok, but over rated. I put my shovel down about 4 ft lower than the build up of sand at the high tide mark & walk a straight line to the top of the dry, dragging my shovel.As I do I occasionally plot my coil in the sand to mark the end of my swing. When at the top I turn around, see my mark, line up and walk back. I walk slow and swing slow and low. Once I work about 50 lines I change it up. I then walk parallel at the top of the high tide line and grid the wet sand to the waters edge. This is good practice to help keep your ground balance stable. Even with my excalibur running from water, to wet, to dry and back and forth can put a toll on it.
I'd rather only work a 1 block section of beach all day than have doubt that by trying to cover real estate I'd be passing stuff up. Knowing that I completely (or at least mostly) wiped out a section, I know that I wont need to go there for awhile and if I do I don't have to worry about faints and whispers because I already went 2 ft down while griding.
My grids today at a local beach. Only found about 5.00 in change and a few silver trinkets before it got way to hot and people started to over run the beach. click the pick to make it bigger.
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