All you need is a 16" midlength gas (18" at most) 6.8 SPC II barrel in 1-11.25 or 1-11 (1-10 will work) twist. AR Performance, Bison Armory, Wilson Combat, White Oak Armory, Rock River Arms, Stag Arms, or any of the custom builders like Ironworks Tactical or Ritch's Precision Guns would provide you with a quality rifle. The 6.8 is good on deer out to 3-400 yards, although mine is set up for short range brush hunting. PRI mags are best for handloaders wanting a long COAL, but are expensive. I use 5 round Kies magazines from Joebob Outfitters for hunting. More info can be found on 68forums.