Another interesting video
To me, what that video shows is just how unstable they are in flight
Almost every pellet shows a damaged section at its impact point, but every one the damage was on a different part of the pellet, which suggests the pellet is "Tumbling" into the target.
I have done a few impact tests with various pellets all against various surfaces, such as my ballistic putty backstop and against steel.
This is one of the cheapest pellets on the market, Milbro caledonion.
The 1st image shows the views from the sides.
Left a Milbr_cal unfired. Middle one fired int