Is that at 40 yards? Did you count the 10" and 20" pellet count? That will most certainly kill a turkey, however, I think from the looks of it that you should be able to do better. It also seems to be a pretty tight pattern without much forgiveness. It may be how I am looking at it but don't look as good as many 20 ga patterns.
I can't speak for the Mossberg and Federal TSS, however, most people are shooting the Carlson's 575. My 870 with hand rolled TSS and a Carlson's 575 throws a wicked pattern. There is no place within a 20" circle that you can put a turkey head and not get it peppered. If a turkey flies off after the shot, it's not on the gun.