How do you true in at 50 with a dove load? Pattern would be all over the place.
I always used 10yds for zero and testing, also saw a trajectory chart with TSS and 1140 fps a 40 yard zero is dead on at 10 yds as well. Not much trajectory of course but dead on is easy to see at 10yds.
My current gun shoots dove loads and TSS the same at 10.