I have found that a sand scoop is pretty useless for recovering targets in creeks, rivers and beaches that are full of packed rocks, gravel and sands. Instead a good sturdy hand pick is lighter than a beach sand scoop and better at breaking up the rock and sand.
Once you have the big rocks removed and gravel and sand broken up from being compacted over thousands of years, you use a technique that I first learned about viewing the Youtube guy gigmaster which you can see in this video. He scoops out the gravel/sand with his left hand and and right hand still holding the beeping pinpointer. As you can see if the beeping stops as he is lifting out the handful gravel/rocks, then no extracted target. He keeps repeating the process until the target comes up with the handful. Pretty neat and efficient. Thanks gigmaster!