I do it all the time. Realize it’s a digital scale and the tare function zeros the scale with the empty case. I even keep a primed empty case of every caliber with its grain weight marked on the side so when I do setups and calibrations I’ll check to see if scale matches again with that case.
When I’m loading a production run on the progressive a QC check is to pull a primed case, tare, powder charge and check the throw. A digital scale makes that check very easy and you don’t slow down the run very much at all.
@9mmGoon , perhaps you did this, but did you weigh your bullets and confirm their weight? I would also check their diameter. Perhaps they’re a bit oversized contributing to pressure. It’s a mystery for sure, but even if 50 reloads in different brass are ok, it doesn’t necessarily point to the old brass as the issue. That’s why I suggested someone else load the old brass and try it.
I got a power pack for my LabRadar since eating batteries is out of the question.