'Griff557' - Howdy!

I suspect the person at "Lee" did not understand that you meant 'Neck-Sizing' and not 'Full-Length Sizing' and did not give your question the consideration it deserved.

To answer your question, I took a Fired W-W .30-40 Cartridge Case, that has been fired several times. (The inside diameter of the 'fired' case-neck measured .310").

I put it in my .30-40 shell-holder and ran it into my 7.5mm Swiss Collet-Die. The Die was adjusted to De-cap the .30-40 Case, (no lube was needed).
There was no 'ball' pulling through the sized case-neck on the way out of the Die.

Most of the Case-Neck was reformed & the Case was de-capped. The rest of the Case Body made no contact with the Die. (The inside diameter of the Neck now measured .3055" to .306"). The Case-Mouth has a slight 'bell' to aid bullet seating. Easy Peasy!

I took a new W-W Case and 'smoked' the Neck in a candle flame. I ran that case into the Swiss Collet-Die with the same result.

Attached photo shows 'Die Action' (rub spots) on slightly tarnished 'Fired Case', Die Marks on 'Smoked Case', and recently loaded 'Neck-Sized' Case, (180 grain RN Sierra - OAL 3.086").

p.s. - I am blessed that my neck-sized ammo fits most of my Krag chambers, regardless of which one it was fired in.

Note - The photo makes the two 'empty' case-necks look larger than the loaded case. This is an illusion.

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