Don't know if it's still available, but I tested penetration of a few different bullets
in water-filled jugs. The .223 Federal American Eagle 50-grain HP had the least penetration of anything tested. I would choose any varmint .223 round and test
in water-filled jugs. The formula is something like 10" of water penetration equals 4" in gel, but Google it. (For me, it worked down to penetration of 2-4 milk jugs being ideal HD loading.)
Load appropriately, and as 'nuther guy said, hit your target.
And have a nice day.
John