Wildcats and necking down

[WKR]

The problem in your case is that Redding bushing dies do not size all the way to the shoulder. They’ve been like that forever.

21st Century makes this tool. There have been others. I have something that this was modeled after but they aren’t made anymore.

Neck Sizing Inserts

We are excited to introduce the 21st Century Innovation Neck Sizing Dies. Unlike traditional bushing dies these dies utilize a special interchangeable black nitride coated stainless steel die insert that will size down to the neck-shoulder junction of the case. The die insert is placed into the...

21stcenturyinnovation.com

Thanks @BBob , that tool did the trick