Interesting to see a number of wildcat cartridges becoming factory loads these last couple years. Variations on this 357/223 chambering have been fooled with in ARs for a while now, some with better results than others. I did my own but based on the 6.8 case and using 357 Herrett dies and reamer in a 1:14 twist .358 bore (I call it the 358 Herrett, very imaginative of course); that one does match 35 Rem ballistics with the 200gr FTX at 2,150 or so.
Nothing wrong with something like this for a thick woods gun; in the right setup it'll be a deer killing machine.
