Got a new DPMS AR15 with a 16" barrel. Looking for the proper scope to put on the gun for coyote hunting. Is putting a SS 10X42 scope on this gun overkill for the guns accuracy? Would I be just as good with a Leupold 3X9? With the larger scope on the gun can this set-up produce accuracy at out to 250-300yds or do I need to get a longer bull barrel if interested in using this gun for predator hunting? Thanks for the input. Todd