The size of the shot you need for turkey hunting will vary depending on the type of turkey you are hunting.
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12 gauge
Forgot your binoculars? No problem. You can use your turkey call as a makeshift set of binoculars. Just cup your hands around the side of the call that amplifies sound and look through the small hole.
20 gauge
A 20 gauge is a good choice for turkey hunting. It has enough power to kill a turkey, but is not so powerful that it will destroy the meat. It is also a good choice for smaller framed hunters who may have trouble handling a 12 gauge.
410
Turkey hunters often choose to use a 410 shotgun because of its light weight and maneuverability. Its small size also makes it easier to carry in the woods and more convenient to store.