hmm..interesting. Just a mix of RF case makes? I've tried S&B, Fio., Win, Rem, CCI, Agulia. Maybe its the fast twist 1:9 barrel, 35g bullets.
I may try them shorter just for the fun of it, but my 95/5 jackets have been working great, Just need to get a 1:8 to test the 37-39g bullets.