Patterning and shot size

[Wacenturion]

You want to try 4, 5, & 6's to see what patterns best with your shotgun and your choke.  Three identical setups can yield different results.  In addition one manufacturer will yield better results in one shotgun while another manufacturer yields better results in another identical setup.   Try at least every 5 to 10 yards between 15 yards on until you find out what works best in your shotgun and what your effective range is ... NWTF says 6 hits minimum, but I perfer 10 - 12 as mentioned above (never depend on the "BB gods" to guide a magic pellet into the brain pan).
 

 

Spend the time doing the above and you will see the difference.  My gun loves 6's (plain old 6's...not heavy shot etc.).  Coupled with a Gobbling Thunder choke, it is instant death.  I never shoot a bird over 35 yards...ever.  Most are under 15 yards.  Turkey guns, chokes, magnum turkey loads etc., does not mean you have a long distance killing tool.  Ethics are far more important.  There is already enough of what I would equate to being sky busting types out there.  Wounded birds are wasted birds.  

[Hangfire]

The above is very good advice. A good pattern and the ethics to shoot only the distance that your gun preforms well at. I have shot birds with high base 12 gauge to 28 gauge high base and several different 12 ga. muzzle loading shot guns. The 28 gauge was to honor my father with his old single barrel Iver Johnson. The birds (2) were less than 15 yards and did the job but I would have liked more pellets in the neck and head. I will not use the 28 any more.  Shoot combinations of loads and shot till you find what works very well.  I often set up a 12 oz. soft drink can and if I can put 10 to 15 pellets in it I have felt I had what would work. The turkey is a very great game bird and addition to this state. I followed the introduction of turkeys in this state and was present to see the first turkeys released at the Cowlitz Steelhead Hatchery, a great memory.

[Smossy]

Id use a samauri sword like they do on the show "Living in Alaska"
He just chops off turkeys heads with his sword, quick humane kill!

[turkeydancer]

      Sorry , samauri sword isn't on this states approved list of weapons - bows and shotguns only.   

[shotgunner]

I would agree that the closer you can get a turkey to come in the better. But, I don't know anyone who is successful at getting their turkey to within 15 yards every time. 30 yards is even nice, but it's not always possible, especially when you hunt in an area where the birds are hunted hard. I have patterned my gun over and over and have a terrific pattern at 50 yards. I use HeviShot Hevi-13 #6 and a HeviShot choke tube. I feel confident shooting a bird at 50 yards and have done so many times without losing or wounding a single bird. It all comes down to using the best products and knowing what your gun will do.

[Limhangerslayer]

I shoot #5's in a 3 1/2"  but always have my third shot a #4  for a little better range if I need it.  Haven't needed to for a little under a year now.