10-Inch vs. 20-Inch Shotgun Patterns
Your 10-inch pattern is important to determine the effective range of your shotgun pattern. If you are getting 100 pellets in a 10-inch circle and that circle is centered on the turkey’s head and neck, you should have a killing pattern at that distance.
For long range shots, do not depend on your 20-inch patterns as a catchall in case you make a mistake. In many cases there will not be enough pellet density inside the entire 20-inch pattern to ensure a clean kill.
Anyone that participates in competitive shotgun shoots could tell you (but they probably won’t want to ) how vital wind adjustments are to keep the dense center of patterns locked on target. If you are taking a long range shot with a wind, don’t attempt a “poke and hope” that the density of the 20-inch pattern will make up for the POI difference. This forum is full of great information on estimating wind speeds. Spend time learning to correctly dope the wind and study your pattern trajectory. Make sure that 10-inch “bullet” is headed exactly where you want before you pull the trigger.