I just use 7.62x54R Russian, FL resize the brass, trim, open out to an 8mm and reload. I am using LEE 8x51 LEBEL dies for the neck and shoulder.
Works fine.
Biggest problem with these was that original ammo used a 244-grain RN bullet. I am loading with 150s and 175s, so it does tend to shoot "just a ittle bit high".
These are a fun rifle and no problems at all with making up ammo.
Go to it.
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