These type of rifles are commonly used in this part of the country for coyotes and prairie dogs. With a good free floated barrel, a trigger job, and a scope; an AR15 can produce 1/2 MOA groups very consistently. Lately, chambering them for the .204 Ruger and the .20 Tactical has gotten pretty popular. There is also quite a bit of interest in the .223 Ackley Improved with longer barrels, but the original .223 is still going strong. You might check out AR15.com - lots of good information.