Originally Posted by Jordan Smith
Originally Posted by drop_point
Originally Posted by MuskegMan
OP said he's using a LCD for sizing the neck - so the INSIDE is perfectly concentric. If the outside is concentric too, then it's good brass - he said it's Lapua.

Originally Posted by drop_point
When you take the case neck and mash it down in a sizing die, the outside is perfectly concentric. The imperfections are being pushed into the inside of the neck. Then you seat a bullet that is encountering those imperfections in neck thickness as it is seated. No matter what brass you use, this is a thing.

Originally Posted by drakecasey
Brass was prepped with a Redding body die, and necks were sized using a Lee neck sizing die. I checked my brass after those steps and runout is basically nonexistent.


Explain to me, if you will, how the Lee neck die makes the inside of the neck perfectly concentric. Explain to me how you can get perfectly concentric Lapua brass.
With a bushing die, the concentric bushing results in a uniform OD of the case neck, pushing irregularities to the inside. With a collet die, the concentric mandrel ensures uniformity of the ID of the case neck, pushing irregularities to the outside.

I was under the impression the Lee die uses collets with fingers over a mandrel. If he is measuring runout on the neck and getting zeros after this process, the inside cannot also be zeros unless he's turned the necks. Even Lapua brass has thickness variation.

"Full time night woman? I never could find no tracks on a woman's heart. I packed me a squaw for ten year, Pilgrim. Cheyenne, she were, and the meanest bitch that ever balled for beads."