When it comes to searching less populated Treasure Coast beaches in search of Spanish treasure, I use a different approach to discrimination.
I use a very minimal amount of discrimination, just enough to knock out small ferrous nails if I am using my CTX 3030
On beaches where I have a chance of find treasure coins or artifacts, I totally ignore the numbers on my display screen and the audio tones.
The reason I do this is because targets on the edge of discrimination range often react totally different to targets within easy detection range, no matter which metal detector you are using.
Many beach and shallow water hunters do not realize that display numbers and audio tones, while reliable at certain depths, fluctuate the deeper the target is.
For this reason it is always best to take a layered approach to metal detecting using discrimination.
Conduct some depth tests on different common targets found on the beach and see how accurately your metal detector identifies them at depth.
When you know how accurate your metal detector identifies targets at depth, you will know how much you can really rely on your discrimination control.
Cherry picking choice targets is great for jewelry hunting but only to a certain depth in the sand.
If your metal detector has a target depth gauge, make a habit of checking out broken high or low tone signals at the deepest depth gauge reading.
You may be surprised like I was when this iffy signal with a maxed out depth gauge reading turned out to a raw emerald pendant.