I found when shooting hollow based bullets in a .58 BilL Large bl. (60" twist, I think) I had to use a lot of powder to get decent accuracy.
With a lot of powder, the skirts had to be thickened up to handle it. Light "civil war-type" loads with stock HB bullets show very poorly and
of course heavy loads needed to get the speed up so they'd shoot in a slow twist, blew the skirts just as Lyman found & published in their book.
This was in the late 70's so I was somewhat using their data, however I did have my own chronograph at that time (since about 1973). The thickened
skirts shot just fine, however I was using 140gr. 2F GOEX up to 165gr. 2F GOEX with bullets to 675gr., the modified #57730(570gr. nominal- 675 modified)
After a while, the recoil with the hooked butt plate kinda got me down. The rifle weighed 11 1/2/12 pounds with the 34" 1 1/8" straight octagonal bl.
The velocity with the 675gr. bullet & 165GR. 2f was 1,325fps and with a mere 150gr., was 1,250fps. I still have that data along with the RB data.