Nosler E-tip is 1.218" long, if you count the ballistic tip. That length needs about a 9.5" twist at 3100 fps.
If you discount the plastic ballistic tip, it is 1.082". Which needs about a 10.7" twist at 3100 fps.
I may need to try the old .257 Roberts go to powder, IMR 4350. I just need to find some and get it.