For all intent and purpose that is correct, but other factors come into play.Debth of rifling, evenhow the rifling was made.

The 1-48 is a do all twist they used to say. They will shoot conicals well and roundball well. The 1-60 and slower are more at roundball but some people shoot minnie ball out of them as well. The 1-28 I found will shoot conicals and sabots but I think for all intent and purpose it was meant for sabot loads. I guess that would depend on the make of the barrel more then anything else. The 1-32 & 1-38 are more aimed at conicals I was told. Then you have a White Rifle with I believe 1-24 twist, yet they are a conical shooting master.

Really you never know what a rifle is going to like as a projectile until you get it on the range. Those broad guidelines I mentioned are only that, guidelines. You still have to push lead through the barrel to see what the rifle is going to do with it.Although with that 1-38 twist in that .54 caliber, I think you could and should have excellent luck with REALs, Great Plains, No Excuse, and Maxiball as well. As for maxihunter, never had any luck with them...