Very good advice, but I take it a few steps further. I start at 15 yards simply to see how large the pattern isn't with my extra full turkey choke shooting my chosen ammo, Federal Black Cloud steel #4. I also checked the muzzle velocity and found with the 28 inch barrel on my 11/87 and the advertised 1600 fps in reality was only 1520, which is still plenty fast to reach out an hit a bird hard. At 15 yards the pattern is slightly more than 10 inches so that aim is critical when shooting in close. Very easy to completely miss a bird if my aim is slightly off. It's also possible to blow a Tom's head almost completely off too. While I haven't done that with a turkey I have done that with a goose that flew very close overhead several years ago. I usually check the pattern at 10 yard intervals using butcher paper and computer printed turkey heads copied on regular printer paper centered on a 24 x 24 sheet of butcher paper. Since the only hits that count are the ones to the head the target does not have to be all that large since what I am really concerned about is where in the turkey's head the pellets are hitting. Anything outside of that target area, especially at farther ranges don't have enough energy left to penetrate the feathers or much if any into the skin. My criteria is 5 pellets into the head/neck area to be considered a kill shot. At closer ranges I use the beak as the target, but once beyond 45 yards the top of the head is a better target area due to the effect of gravity on the shot. I've found that killing shots are usually consistent out to around 55 yards with some still possible out 70 yards if shooting downwind, but sometimes only 50 yards if shooting into the wind. Crosswind effects seem to be negligible.I pattern at 25 first, then 40, because turkeys never cooperate with your preferred distance.