Having a few issued with the 121mm press fit BB and fitting Hope cranks on alloy Beargrease.

My understanding is that with the 100mm fat bike axle fitted, Hope cranks would fit fine in the 121mm BB shell, but i have cinched the cranks arms as tight as they will go on to the axle (converted standard Hope cranks by buying 100mm axle for them) but there still seems to be a good 4-5mm side to side play as if the axle was that bit to long?

Any ideas please?

You transferred the bearing preload ring over didn’t you?