1F should start the shot off more slowly, thus damaging the shot less thus just in that, improving patterns.
I see what I consider too many holes in the patterns pictured. Yes the Turkey was "killed" in each target shown - but by moving the target a mere 2 or 3 inches one way or the other, at least the 40 yard turkey would not have been hit in the head or neck. Pattern evenous is very.important as well, if shot that will not pen. the feathers to create a vital wound is used.
Just a thought.
In loading bp in ctgs I find instant pattern improvement over smokeless.
One might ask WHY?
Is it because of lower MUZZLE pressure perhaps?
This would suggest a faster burning powder like 3F that was used up and dropping pressure by the time the " load" made it to the muzzle would be better. Since we've heard here that 1F patterns better, perhaps that argument doesn't hold water - or, other variables are at work.
Much testing is required in EACH different gun to get THE best results.
Perhaps those who have achieved good results in at least one of their smooth bores, could present THEIR list components, either here, or in a separate thread, perhaps entitled Smoothbore Shot Loads.