Thanks for all the helpful replies.
I guess my main confusion is around what to size to. Seems pointless to bump the shoulder back further when its still chambering at the fired length.
Brass is around 3x fired, so not brand new.
Have been doing a lot of watching and reading (pretty much everything that has been suggested), but can never seem to find what to do if your fired brass size still has a whole lotta length that it will chamber with.
As I say, thanks again and I'll give some more things a try and see how I get on!
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