I've swaged thousands of .224 bullets useing spent 22lr caseings as the jacket. I'd swage them leaving the tip open (HP) to get fast expansion, or i'd put then into the die backwards and swage them into a kind of FMJ.

All of these bullets were shot in my 222 Rem./12 ga. combination gun that i've hunted small game with a lot and i always carried both types of ammo with me. I could use one or the other depending on how much penetration i wanted depending on what i was shooting at...

DM