Hi Adam, I use my old Redding 222 type-S die for my 20-222s and a cut down Redding 20 Tac FL die for my 20 Thunderbolt. The Duster/Bobcat versions will require a different neck die as their shoulders are indeed more blown out than a regular 222 die. A 20 Tac type-S die "might" work, you would have to measure the shoulders.
For my 20-222 I used an existing print that was perfect, just the way I would have speced it. Dan C helped out it together for another member years ago. For the 20 Thunderbolt I did my own. If you need either print send me an email at
wb323@comcast.net and I can email them to you. I think a .232 neck is perfect for the new Lapua cases if you want to do a slight cleanup on them. If not, you'll need a .233 or .234 neck depending on how much clearance you like.
BTW, as a leatherneck you'll appreciate I met my French wife at Belleau Wood. Been to a few parties there with various past Commandants.
ps my box is often full here
-Warren