I doubt this ever gets past the "thought exercise" stage, but here goes. I'm trying to figure out how to make a set of .224 bullet swaging dies on the cheap from 7/8-14 grade 5 (or grade 8) bolts, or Lee bullet sizing dies. These would be for reloading .223 or 5.56 ammo for a carbine. I do not really have a machine shop, but I do have a grinder, a dremel tool, and a cheap drill press. And time.
The Lee .224 bullet sizing die should work OK for derimming .22LR's to make jackets with very little modification.
[brainstorming mode]
Now, how to make the cores precisely enough (I don't suppose they could be cast directly into the jackets with a nose-pour mold), and how to make a pointing die. A lap could be made from a .224 FMJ bullet and clover compound to finish the pointing die after it was roughed-in somehow...
Half-jacket bullets might could be made from .22 Shorts. That might be the best solution; the cores and the ogives could be cast into the jackets, then trued with a pointing die. It done correctly, the entire bearing surface would be brass...
Is this a ridiculous idea, or does it have any merit at all? :) I like the idea of threading the top of a .224 Lee sizing die and making an insert from an annealed, ground, and rehardened 1/4" or 5/16" bolt. (how to get the bullet out without unscrewing the top every time...) The same die could then be used for derimming and drawing jackets, and pointing the bullets.