That makes sense and I totally understand that disclaimer.
The rods I obtained are rated with a permeability of 400, which I believe is the same as the Russian surplus units.
Unless there is some other characteristic to compare and differentiate them, my hope is the ones I got are electrically identical to yours.
Either way, I'll start with 27 turns and experiment a bit before permanently securing the winding. Thanks! >>>
If it were me, and if I was cutting the expensive 1162/46 Litz wire to make an FSL coil, even if the Chinese manufacturer says that their ferrite rods are the same (400) permeability as the ones I used, I would cut the 1162/46 Litz wire a couple of extra turns longer than what I did for my existing (Russian surplus ferrite rods) FSL, to account for differences in manufacturing tolerances and measurements.
Otherwise you would need to splice the Litz wire, if you cut a coil too short (to tune down to 530 kHz). Splicing Litz wire is never recommended, since each individual Litz wire strand is designed to have its own performance potential throughout the entire length of the coil.