The “Big 3” turkey loads include Federal Premium, Remington Premier Magnum and Winchester Double X Magnum. Three-inch loads have always done a fine job for most turkey hunters, but some prefer to use the heavier 3 ½-inch loads in new guns chambered for them. New high-velocity turkey loads have ¼-ounce less than shot than standard magnum loads, but they produce 150 to 175 fps more velocity to reach out and touch toms at further distances.
You should also take a look at the new tungsten-nickel-iron loads offered by several ammo companies. The pellets, which are heavier than standard lead beads, pattern densely in many shotguns. Tests show they provide awesome knockdown power and penetration to anchor gobblers out to 35 yards and beyond.
Should you use No. 4, 5 or 6 shot for turkey hunting? Truth be told, it really doesn’t matter. Purchase four or five different loads with various shot sizes. Hit the range; set turkey targets at 20, 30 and 40 yards; and test those loads through a couple of super-full and aftermarket choke tubes. Then go out and smoke a turkey with the load that patterns best in your gun.