Odd gauge shotguns or smooth bores tend to be the red-headed step children in the gun world. Most loading data is given for only EVEN numbered gauges.
You can use most 12 gauge loading data you find for your 11 gauge gun, except, of course, the wads and cards. Go to the Black Powder Notebook site that Bob Spencer( member Spencer10, here) has. He has a wonderful article written by V.M. Starr on shotgun loads, with very good advice and loading data for a lot of gauges.
if the load you mention patterns well, and doesn't hurt your shoulder, you are set. Just determine the maximum distance where your pattern will leave an average of 5-6 pellet hits on the head and neck of a turkey, and then mark that distance off with a couple of stakes measured from where you will be sitting. Call the bird inside those markers and aim well.
It the barrel has NO choke, you will probably be restricted to 25 yds. or less. 75 feet is a relatively short distance for even a slow moving load of shot to fly- time of flight is negligible. In that case, you can often get denser patterns and lengthen the maximum yardage by reducing the powder charge by 5-15 grains. Reducing the powder charge will also reduce the felt recoil, as will reducing the load of shot fired, by 1/8 oz. increments. Out to 30 yards, I should think a 1 1/4 oz. load of shot will produce adequate killing patterns.
Pellet energy down range is what allows full penetration of the game bird's body, including the difficult task of passing thru layers of feathers. The reason to go to larger pellet sizes( #5, and #4 shot) is to let the added pellet energy these sizes have over #6 shot do the work that the smaller sized shot requires more Velocity, and More pellets to achieve. When-- for any reason--- the shooter is RECOIL SHY, reducing velocity and load weight, while increasing pellet size is often the solution. :hmm: :thumbsup: :thumbsup:
