I have the Lyman lubrisizer with heater and have made about 1200 9mm 120gr truncated cone projectiles. They have all already been loaded and shoot great all sized with a .356 sizing die but with some leading I got to looking for the problem and I have found that my sizing die is actually sizing them to .3555 I did pull a bullet to be sure it's not be sized by the case and went ahead and measured a fresh sized one to get that measurement. I just want to know if this is standard? If I buy a Lyman .357 die will they come out .3565?
Not complaining as they do all shoot great and accurate and the leading isn't bad to me I'm just curious about the sizing dies. I do get that technically if we're rounding then they are .356 Has anyone else noticed this?