Neck Thickness

Redrock

Steve Grosvenor
working on a 30br with Lapua Cases what is the neck thickness after done turning and coal w/118 bibs 7degree
 
"Robinett" reamr design"

If you have a chamber cut with a .330" neck...then you can cut your brass neck wall thickness to .010" maximum..I have a loaded round neck diameter of .3285" when used with a .010" wall...You can turn them slightly thinner if you need to clean up some thin necks...;)

Recently, I have encounterd some Lapua 6mm BR brass that had a lot of variation in neck thickness...and flash holes off center and partially blocked with burrs..:eek:
I usually fire a 6mm bullet in a 30BR chamber to create a primary formed 30BR case, but I am now seeing uneven (irregular) spots in the inside of the case necks when turning..I get variations of .001" from spot to spot on some case necks...
I now recommend Expanding UP the 6mm neck to 30 caliber to "iron out" the irregularities inside of the neck wall..transferring it to the outside of the neck so it can be cut true and even...
 
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