I've had .58's with 48", 56", 66" and 72" twists. They've all shot very well with nice snug loads and appropriate amounts of powder.
The 66" twist Hawken I had shot best at 100 Yards, with 140gr. 2F GOEX, while the 72" twist shot best with 120gr. GOEX 2F. At that time
I also tried C&H 2F- late 70's powder and to match the 140gr. GOEX load, I used 180gr. of C&H. Lyman's BP handbook was spot-on to my
chronographed loads using my Oehler #12 machine, with both loads, 140gr. and 180gr. making 1,800fps average.
Just goes to show that you actually have to experiment to find what the gun likes - if you are interested in finding it's best load.
A fellow from Terrace was at the range when I shot a 5-shot group with the 66" twist .58 Hawken and upon retrieving the target,
offered me enough money for the rifle right there, that I could not turn it down. That was a Bill Large barrel which usually ran 1-1/2"
at 100yards. That rifle also did 1,365fps with a 675gr. modified Minnie using 165gr. 2F GOEX. It also kicked very hard with that narrow, pointy
butt plate. The barrel was 1 1/8" straight octagonal and was 34" long.