I'm not sure about the 54 but I have the 50 hunter barrel along with a 54 round ball barrel for my Great Plains. I get very good results shooting conicals out of the hunter barrel, some loads were under .5" at 75 yards. I have not shot a lot of sabot rounds out of it but the ones I have were decent to good, 2" or less at 75 yards. I haven't shot it much lately due to traveling for work so I need more time to develop some loads and explore it's range of powder cappabilities with each bullet. There are sabots for the 54cal that will work with most bullets that work in a 50cal so you do have options to try out in it. Good luck and keep us all informed.