is it possible to use a .222 die for a .223? i know youo couldn't do a full case resizing but I would think that you could do a partial resizing especially the neck.

Take a look at the case dimensions. It appears to be possible to neck size but you'd have to be pretty careful not to bulge the shoulder.

I would think you could neck size without any issues.
can you neck size a 7x57 case with 7mm/o8 neck die? same sort of issues to contend with I do think. depriming the 223 may be an issue as pin may/maynot be long enough.

Shouldn't be a problem as long as you are careful to adjust your die to neck size only (as Pumpkinslinger suggests). From earlier posts it appears that you also load for the .222. Constantly changing the setting of your die between .222 and .223 will quickly become a pain! Might be a better option to haunt the local gunshop and see if there are any good, used dies for the .223 available...but even new ones aren't expensive.

Just something to keep in mind !!!

Trying to neck size with a full length die will sometimes disrupt the headspace dimension.
This is possible if the body of the case makes contact with the die before achieving the amount of neck sizing required/wanted.

As brass is re-sized it flows toward the neck relocating the datum line, as you reach full stroke of the ram the datum line is re-positioned back into place.
All this is dependent upon how much sizing is actually happening.

I agree with SSL...........get another set of dies !!!

I know its not the answer to the original question but just an FYI. You can handload ammo for a .223 using .221 Fireball dies and it works very well.