I reload 17H along with many other cartridges. I have neck sized in the past, but now full length size for every case all of the time.
Neck sizing only introduces inconsistencys eventually as you will need to bump back the shoulder at some point so you will end up with some ammo thats neck sized only and some that has the shoulder bumped back or FL sized therefore changing the case capacity.
Best to FL everytime and only just bump the shoulder by the bare minimum needed.
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