Targeting and Patterning With a Shotgun
Before you start hunting with your shotgun, you must be able to properly estimate range, and determine your maximum effective range as a hunter. This is the maximum range at which you can effectively and accurately take down game. Shooting at game that is beyond your maximum effective range will likely cause you to either miss the target, or merely wound the animal- which is against the code of hunter ethics.
Patterning a shotgun is a very important element in finding out how the shot charge is being affected by the load and choke. Shotguns are usually used for moving targets and are generally pointed at a target, not aimed like rifles.
To pattern a shotgun, you will need to go to the range bringing with you your shotgun, shotgun shells and some pieces of paper at least 40-inches square. When you pattern your shotgun, be sure the ammunition you use has the appropriate size and type of shot or projectile. Using different ammunition will affect the outcome of the pattern. To assist in centering the pattern as much as possible on the paper, draw a black 2-inch dot in the center of the paper. Place the paper against an appropriate backstop at the maximum distance you expect to take your game (the maximum distance should be no more than 40 yards); be sure to measure this distance accurately. If your pattern is found to be effective at the max distance, it becomes increasingly more effective the closer to the gun at which you shoot your game.
Step up to the distance line, point at the black dot and fire. Then walk downrange and draw a 30-inch circle around the densest registration of the pellets on your paper. This is roughly the size of an animal's vital area (heart, lungs, liver).
Count the number of pellet strikes inside the 30-inch circle, and compare to the total number of pellet strikes on the paper. The percentage of pellets within the circle needed for a clean harvest will vary depending on the shot type and size and the game hunted; so consult the manufacturer's recommendations.
To accurately evaluate your patterns, you must fire a minimum of three patterns of each load, shot size and choke at each distance of interest. This means one shot each at each of the three sheets of paper for a total of three shots to be averaged; never fire more than one shot at each sheet of paper.
Shotgun Pattern at 10 Yards
Shotgun Pattern at 25 Yards
Shotgun Pattern at 40 Yards
IMPORTANT! NEVER fire at a target that is found to be outside your effective range. It is both dangerous and unethical to do so.