So many great choices the 223 is probably one of the best out there.
If you're into reloading one of my favorites is the 19 Calhoon created by James Calhoon from Montana, 22 hornet necked down to 19 caliber. Calhoon offers a good selection including 27, 32, 36, and 40 grain bullets. The 27 grain flies about 3,600 fps and the 32 grainer about 3,300 fps, very accurate cool shooting P-dog cartridge. He does a 19/223 that's a real screamer too.
