IMHO you need to get out and shoot that load and choke combination to see how it patterns at various yardage.
The longest shot I've made to date with my 835 with a super full choke and 3"-4x6 copper coated duplex turkey loads was 45 paces. This was back in the early 90s when I first started hunting those Thunder Chickens. At any rate it was exiting because it was my first turkey and my second year hunting.
I did not have the patients in those early days of turkey hunting that I have today and probably would not attempt a shot that far anymore because I have a few fans on the wall now. I try to stay under 25 yards and I don't use a blind. I'm now in it for the challenge.
Those shells may travel 75 yards but I'd hazard to guess they will only bounce off a turkey. Believe it or not those toms are pretty hard to kill.
By the way, when your patterning those 3.5" shells, wear heavy jacket cause they'll beat you to death. Shoot Straight and be Safe, Joe
God, Family, Guns, in that order.