Most of the loading for this caliber has been with H4350, I have seen loads with hybrid 100. H4350 has been difficult to find, however there seems to be some of the imr4350 available.
I have read the debate regarding are the powders the same or not, reviewed the loads, and IMR seems to be different and in most cases required an extra grain of powder over the Hogdon variety.
What is your load with IMR4350?, has it been successful?, how is the pressure?, and were you able to load what you need in the case without compressing the load?