I used milsurp LC54 30-06 brass to reform to 8mm-06 . I also used TW brass and resized and rough trimmed with a arrow shaft cut off tool before trimming to length 8x57 MM Mauser. Neither have caliber designation on them to be confused with 30-06 ammo . For the 375-06AI, I use RP 30-06 brass but that easily stands out and no way would bolt begin to close on a loaded round let alone an empty case
I tend to use what I have ,but at same time keep the boxes they are in well labeled with caliber , load data and what gun they are for . As I like to keep all fired cases matched to the same gun . With the exceptions of handgun or shotgun ammunition.