I tested some of Nielsen's new little high speed press made 23 grainers today with my Lelya. To my surprise, these were deadly accurate out to at least 175m with a light crosswind.
My Huma regulator was only set to 127.5bar and I did not want to open up the air tube with all of the dust. I turned the HST down to the high point of the power "knee" for an 841fps average (
840-842 / 39 shots). My LabRadar wasn't providing reliable data today, but I would conservatively say the BC was 0.074 or so from muzzle to 35m (I primarily used my EdGun chrono for tuning).
As far as groups went - they were not hole in hole (except for my 35m zero), but they were grouping 1.5-2" at 100m, 150m, and 2-3" at 175m. Some of that was wind and parallax from my 1-8 scope, but they're accurate enough that I would use them for hunting grouse and turkeys.
I'm actually more hopeful for these new 24.something grain cup back slugs. I ordered 4 boxes to test out with my Lelya and Crown(s).