This isn’t exactly news unless hollow points are specifically banned Norway. I’ve got my Speer Reloading manual in front of me and the grain weights do not change much if at all between hollow points and FMJs; however, Ballistic Coefficient does change.

In ballistics, the ballistic coefficient (BC) of a body is a measure of its ability to overcome air resistance in flight. Which can have impact on accuracy at longer ranges. Hollow points and flat nose bullets tend to have lower BCs than a FMJ. Unless we are talking about match grade HPs rifle bullets. The HP is tiny compared to what most people would think of HPs.

Dum-dums in the true sense are FMJs filed down often by hand and they tend to loose accuracy do to uneven differences by filing.