Neck turning.

I never turn to less than .013”, even with a sloppy chamber or a ‘neck turn only’ chamber. I used to turn to .012” in my comp 300WM, it was too thin and caused premature cracking.
Nowadays, I only turn to clean up the neck, I don’t turn to a desired diameter anymore, no need, as long as the brass cleans up for about 80% of it’s length, good to go, as I don’t size the entire neck either.

Although I personally resize the whole neck for my application
0.0105 seems too thin unless you have a bushing die that is small enough to compress the neck far enough to hold a bullet well. I turned some 7RM at 0,011, brass was thin already I think and I was just cleaning it up so it was even, and my standard die would not size the neck down very much. The loaded bullet was barely snug.
I'm using rcbs bushing dies.
Well. As a number, 0.0105” is probably not too thin, but it is borderline. to me normal on a no nt chamber is about 0.0135”. I’ve see nt chambers as tight as 0.008”, but I think 0.012” is more common for nt chambers. Mind you these are generally tight neck chambers like at .262” neck in 6mm.

Cutting a 30 cal …..well, the brass is supposed to be 0.015” for a loaded round diameter of 0.338” in a factory chamber running 0.343”ish. When you have a 0.343” chamber or abouts, you don’t want to cut thinner than about 0.0135, IMO. That is because firing and sizing can overwork the brass pretty quickly with it moving so much. Annealing helps, but… can see we are just going too far down the rabbit hole. If that doesn’t clean them up 80% or so, toss those cases. They are just too bad….aka Winchester.

They should have started at 0.015”ish…..right? What diameter cleans them up 80% or so?

Honestly, buying Lapua, ADG or Peterson brass will be an easier “solution” and are not as expensive as we think!
Cases are starting out around .014"-.015"

I'd need to turn another one to see where 80% cleaned up would be. Not a big deal to do, mandrel us still in the lathe, but I think I'm done fooling with it.

I've been thinking about going the expander mandrel route for a while now, maybe I'll just try that.

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