"Effective Depth" - Question

Hiya Tom (or anyone else that can answer this!):

Recently read through "Fisher Intelligence" and was particularly curious about the "Coil Myths" section. In one section you write that an 8 inch coil might have better "effective depth" than an 11 inch coil because the larger coil will be struggling to compensate for the increased volume of mineralized ground.

Very curious about this because I am planning on using my CZ-6A in the wet-sand/shallow water of a saltwater beach that I know has plenty of black sand. Was planning on buying the 10.5 inch coil for the detector because I understand that alot of people use it at the beach, but now I am not sure that it would be suitable for the area that I want to detect?

Any coil/settings advice for shallow surf saltwater beach hunting would be appreciated.

Thanks! Love all the info buy the way! Best, Crabman

I think because the CZ line only use concentric coils
rather than DD coils volume is multipled to a greater degree.

PS the Sunray S12 is great if you can find one

This is a trial-and-error method for salt beaches. You CAN (somewhat) mitigate some of this problem with the 10.5" coil by running in all-metal (auto-tune) mode......Sens on '10' and Vol on '10'. I would moreso recommend this vs. the smaller 8" concentric coil in the ID mode. If the ground (black sand) is severe; yes, by all means, the 8" coil will ascertain greater depths. Remember, you are not too concerned (whilst beach hunting) with target separation/masking.