To my astonishment I found some Lapua 223 match brass in my stash. Brand new in the box. I decider to form into 222 for my favorite varmint rifle. The brass was match prepped at the factory and the cases were necks were trimmed for concentricity. Sharp looking brass!

I took 20 rounds and ran them through the 222 fl sizer and ended up with a neck with two obviously different diameters. When pulling the case out of the die the expander ball seemed to hang up on the neck, perhaps a dreaded doughnut?? So I need to trim the neck obviously. Would you outside trim first? Trim inside first or shoot then trim?

The pic below shows what I’m talking about. Left to right is a 223 round out of the box. Middle: after running through the 222 fl die. Note the “bump” in the neck from where Lapua trimmed the neck. Excess brass at the bottom half of the neck. Far right is the brass after I trimmed to 222 length.

Just wondering what the correct order of case prep should be from this point in. Thanks for your suggestions!

Years ago I formed some out of Military LC brass and it sure did not look like that.
I looks like the neck did not properly size all the way back to the front of the shoulder.
Sitting here looking at the picture I an not figure out what has happened and which is located at the correct dimension

I sized the parent case first in correct die and punched out primer. Then ran through the die of case I was making with decapping rod removed. I trim afterward. Lubed well of course. Then trim to length. Anneal afterward.

Looks like to me that you need to adjust your die or do this neck down to 222 in several steps.... with a die adjustment each time..

I do this necking down 223 to 20 Practical.... its not a single pass neck down... especially when you get into small diameters.

Have you tried seating a bullet or pushing it into your chamber? Sure seems odd it didn't size all the way down to the neck junction....

If it goes into the chamber okay, then possibly seating the bullet will push the case out to full size at the small section. If it doesn't go into the chamber it looks like it just couldn't quite form the neck that far down and pushed the neck down into a balloon shape below the formed part.... you might try greasing it up and running it through the die a time or two more to see what happens...

Lapua turned the neck on the 223 brass. The “fat” portion on the bottom half of the neck, post sizing, is what used to be the shoulder on the original.

Best advice I can give...........Fhuqk what you are doing and just buy Lapua 222 Brass........
been using it for years and it's awesome !!!!!!!!!!!!!!

Okay, I can see that now. Just couldn't seem to get my head wrapped around it for a bit....

Seems like it if the internal dimension looks okay now, you need to turn the outside of the neck? Or run them through the die several times without the inside neck sizing puck in place and turn the insides of the necks one you get the outside massaged?
I"m starting to think boatanchor has the right idea- get new brass....