Unfortunately I had to stop the tests. My supply had some burnt smell, even no problem while runing. I called my supplier, who did that special power supply for me (mine has 48V 20A and 12V 5A at the same power supply, in order to run the zvs and my other parts of control). I stopped the tests at 7.5 seconds, almost anealled 308 brass (almost glow red) but still I see that might need some more ms or seconds to setup and reach the proper anealling (I don't have access to temperature painting here like many others do, so I am running it by now just checking the small red glow target).
With the new setup I'll try after I receive the new power supply, I'll decrease 1 or 2 turns (maybe inner turn or outer turn) testing the current aiming to 16A with 308 brass at half coil height position. That might be perfect setup. Hope to give some good news soon!