It helps a great deal to have some "cheap as well"surveyors tape strung up on a metal rod or in a tree limb throughout the course of the range. I can shoot 325 yards behind the house here and I have several windflags that I set up as well as putting the streamers in the tree limbs. I can shoot better WHEN the streamers ar in the trees VS> when they are NOT. Its amazing low much LITTLE wind affects the bullet flight.
If you are able to put the tapes on long metal rods or in the trees, try to shoot when the flags look the same each time. Be patient and wait for it. YOu'll be amazed how much smaller your groups get. Steve has an excellent point. You need to have a dot or a "corner" or edge of something on the target that you can easily put the crosshairs back on.Higher power the scope the better. It may be hard for you to see bullet holes at 300 with a 16X. You should be able to see them at 200 though. Good luck, Sam