sluging barrel question

[desteve811]

I have slugged most of my guns today. Now how do i determine which sizing die to go with? For example, My 30-30 measured out to be .305 from groove to groove. Do I want to purchase a sizer slightly bigger than .305?

[44man]

I have slugged most of my guns today. Now how do i determine which sizing die to go with? For example, My 30-30 measured out to be .305 from land to land.
When you measure a slug, the largest dimension will be groove to groove. This is what you want to fit. Don't fool with the small measurements of the lands.
If you have the groove to groove size of .305", just shoot .308" boolits.
You MUST use a good micrometer that will measure in .0001" to be accurate. If you are using a caliper you will never be right.

[desteve811]

so if i have a bullet mold that drops .311 bullets, I would want to size them to .308?

[HORNET]

That would be a good starting point (.308). I'm personally skeptical of that .305, but I've been wrong before (even got married once). If the barrel leads or the grouos won't get better than patterns, you can always polish the sizing die out a bit. Taking metal off is easy, growing it back is MUCH tougher.