When several people search a beach with the same type of metal detector, often the only real edge you have is your metal detector settings.
I make a point of never telling my competition the metal detector settings I use on my local beaches, especially if we are using the same metal detector.
Having taken the time to conduct target tests on the beach with my metal detectors, I see no point in helping the competition to increase their gold finds.
Luckily their are plenty of generic, one size fits all settings passed around on the internet metal detecting forums for every metal detector.
If you want to get serious about beach and water hunting, you have to tune your metal detector to every beach you search.
Have a few control setting starting points, but take the time to push your metal detector controls.
Never just use a bunch of set and forget metal detector control settings, leave that to the other guys.
We have a hobby where an inch or two can, and often does make a big difference in your treasure finds.
The difference between going home with an expensive piece of jewelry or old artifact, or leaving that same object behind for the next beach hunter who has tuned their metal detector correctly.
People think it is bravado or bragging when a person says they found jewelry following another beach hunter, often it is just a case of having the edge of using better metal detector control settings.
That may explain why I was able to retrieve this nice chunk of 18K gold with precious stones recently, when two other people had searched the area only a few hours earlier.
Never under estimate the importance of testing and tuning your metal detector, especially when the competition is using the same metal detector.