The 55 Hornady SP with cannulure is a great 223 bullet. It’s not as soft as a real varmint bullet at 223 speeds and acts very predictably. You can count on 10-12” of straight penetration with a 1.5” wound channel. I’ve killed a bunch of pigs with them, my favorite cheap bullets for knocking around truck gun use.
The 55 Speer SP is softer and doesn’t give as much penetration, but it kills well on broadside shots.
