Re: .223 rem Neck I.D. after sizing ( Help )
Depends on how much neck tension you're going for here, but I'd run around .222" or .221" at the absolute smallest. For a bolt gun where the ammo wouldn't be subject to too much rough handling, I wouldn't balk at .223" or so. At .215", that's way too tight. You're going to get very short case life, and accuracy will likely be an issue as well. Check the size of your expander ball, to start with. To get a real handle on this, you might want to take a look at the bushing dies, like the Redding Type S dies. These have interchangable bushings (hence the name; duh!) that can be had in .001" increments. With these, you can set the neck tension very precisely, and not overwork the brass like the current dies are doing.
Another option would be to take a look at Sinclair's expander or turning mandrels. That will solve the trimmer pilot issue, and help uniform the neck tension better for you; still will be overworking the brass, and that's a different issue.