I would weigh some samples of each headstamp sized and trimmed brass to see which ones are similar (similar weight and outer dimensions implying similar case capacity). When I did that I surprisingly found LC, PMC, Remington, and most other milsurp brass weighed I think around 90 gr, and Federal and IIRC, Fiocchi, were just over 100 gr.
I keep the 100 gr brass separate and download it by 0.5-1.0 gr depending on powder/bullet. And I keep my LC brass separate for accuracy loads. All the PMC, Rem, and milsurp gets bagged together for plinking.
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