Sizing Question

[jsteed]

If a Lyman mold casts a .308 at the predicted .310 useing WW, and most shooters (30-30) prefer the sizing to be .311, it seems to me a .311 sizing die would be too large to do any sizing. I haven't started casting yet but just trying to get my head into it. Feedback please !!

[462]

Start with your rifle's groove dimension (slug the barrel and measure the slug with a micrometer) then determine how much larger than that you a want your boolits to be -- .001", .002", .003".

Too, who knows what size boolits the mould will produce. I have a .30 caliber mould that drops .314", another .309", and another somewhere in between.

[jsteed]

So, I need to know the actual dimension of the mold casting, right? And rifle groove, correct?

[1Shirt]

Trial and error process. That said, for most 30-30's .310 will work fine. However if there is leading and and you are using a good lube, moving up to .311 may correct the problem. Also consider the factor of the sizing being able to chamber. Some 30-30 chambers might be tight and not be capable of accepting .311.
1Shirt!