Become famailar with your rifle and it will become an extension of your arm. Nothing like famailarity to become a deadly shooter.
^^^ This, definitely.
Even if you enjoy shooting other rifles and trying them out, IMO if you don't have one "go to" gun that you'd grab out of a stack of 20 then you haven't shot enough to find that one and become comfy with it.
I've read three books lately -- Damn Few, American Sniper and Lone Survivor -- and having that intimate familiarity with a rifle resonated in all three. The same is true for hunters, I think, or good hunters.