Brass annealing hardness - scratch test?

[Zeneffect]

Not trying to be silly but if you're going to that much effort to investigate proxies for end results, you could just determine the best induction settings by the end result itself.

Separate a few batches of cases and see which temp gives you the most reloads, and/or smallest groups.

I have noticed some variability due to environmental factors. Though the end goal is to increase accuracy and extend brass life I'd rather determine the annealing by a repeatable hardness value then track times by ambient temps (which can range from 40f to 110f) cold days require more time obviously... I could probably mitigate this by switching to a plastic loading tray as it won't act like a giant cold heat sink like my aluminum one does.... then again it won't act like a giant aluminum heat sink and I'll have to change the time anyways... which means I'd have to figure out the timing again.. and my method is a pain in the @$$ using 120fps video capture (to determine time to silver flash)

Regarding w-20 vs w-20b



Notice the minimum dimension of .6mm is maintained with both. Anvil size changes otherwise same unit. Calibration requires pressing the probe into the anvil and adjusting the scale to 20, so dimensionally it has to work otherwise it would be impossible to calibrate.

Same mods will need to be done. Need to clearence the plunger/indenter. Need to grind down anvil on 3 sides if I want to use it for 5.56 (though far less... .25 left and right, .5mm bottom is 10 min of hand work with a file)

Current anneal time for lapua brass is 1.52s in 60-70f using induction. 6 coils, about 2mm air gap between case and coils.