When shooting to kill with my 5.56; I prefer to send jacketed soft points down range. The expansion will easily stand toe to toe with any hollow point or ballistic tip, while allowing more penetration. Personally I have shied away from buying any hollows for rifles. ( I just feel there are better options available for the priced per round of hollows)
After buying my AR, I picked up an impressive variety of different rounds in different weights. I suggest you do the same. If your LGS does not carry any JSP in 5.56, look online you will not be disapointed dealing with these folks.
look into their DRS reloads, I have never had a problem with any of there ammo, and at the PPR i would like to think they are one of the best deals currently available for brass cased ammo.