It is true that in many cases a cast boolit can use more powder then jacketed but I will never say that because of a few experiences with more then a few powders.
One example was a moderate load of 4198 in the 45-70 using a jacketed bullet. All was fine, shot good. I went to a cast GC boolit of the same weight, hard lead. It shot decent at around 1600 fps, then I had a few that spiked to over 1800 fps and stuck brass. (Between a group one and two load.)
Now there are a lot of reasons this can happen so I won't list them and did not want to try and fix it so I changed powder and have had no problems since.
It is one of those things we can never predict and will not be found just working up a load because you can shoot a lot of what you think is OK---until that one.