I find the DPMS standard weight barrels to be more then accurate for our game ( 1 moa )
I have heard that the Oly Arms barrels are an excellent value.
BTW, to have a 20" cut and threaded for a comp can be had for $45 so if you can pick up a used 20" of the classifieds over at AR15.com, you could be in pretty good shape $ wise.