Thanks D.
It's a simple but expensive and labor-intensive process. Have a couple custom ground Creedmoor reamers built with .261 and .251 necks, then find a die manufacturer or smith to ream you a couple Creedmoor non-bushing die blanks. You don't want to use bushing dies as they leave alot of the neck unsized at the neck-shoulder junction that will be too thin after neck turning.
With your Dillon 1050 and your custom-built dies you can successfully make this brass on your own with very little run-out.
My virgin, pre fire-formed TIR (Total Indicated Run-out) at the necks is consistently between 0.002" and 0.0037", which means my actual run-out is half that.
Starting with Lapua 6.5 Creedmoor brass:
- First step thru a factory 6 Creedmoor FL non-bushing sizing die (I highly recommend Forster)
- Next thru your non-bushing .261 neck FL die
- Next thru your non-bushing .251 neck FL die
- Then finally thru your .22 expander mandrel
- Turn necks
- Anneal
Or you can buy mine at $240 per 100. Seem fair?