TargetTalk

Leon wrote:I honestly think that using any reasonable quality die with the factory expander will be OK. Us normal shooters would not notice a difference....At the super elite level, with perfect technique, maybe...

You would be best spending your time improving your shooting technique that fixating on expander sizes

Nooooo...
It really is critical, I've done the tests, even at 25m. It can be the difference between a 25mm group and a 125mm group.

Thanks again all. I have just received all the Dies minus the Lyman.

Lee oversize sizing Die , NOE insert for the Lee die and a Lyman neck expander in 32EP which I guess stands for European projectile. The lovely lady at Lyman did not even know such an insert existed but asked a technician and he told her about it. I ordered 4 of the inserts which they manufactured for me as they hadn't made them since 2016. No extra charge was made for this !

Will start loading at the end of the week. HN .314 with V310.
For the final case mouth diameter ,shall I copy an original cartridge or measure the brass thickness ,double it and add .314 giving a perfect straight wall?
Thanks again for the wealth of advice .

Keep the crimp as light as possible, still feeding reliable.
Go from there to seek accuracy.

I have had better results with a roll crimp but others who are,(in the game, knowing what they are doing have had better results with a taper crimp. In my gun, by the time a taper crimp would feed reliably in my Benelli it was too tight for accuracy. Either way as said in the post above, don't disturb the front of the case any more than absolutely necessary.