I reload 762x54R all the time, but only lead bullets. The best mould for mine is the Lee C312-185-1R. With 26.5 gr of H4198 I get 3/4" groups at 100 yards. With 25.4 gr of I4227 I get 1/2" groups at 100 yards. I bought some PPU brass years ago and no telling how many reloads I have on them.

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