One thing I learned here for certain is the big 22's are not well explored territory.
Depends on which aspect of the problem you look at. From the standpoint of internal ballistics, the cartridge is old hat, for it is the ballistic twin of the .257 Wea. They have the same case capacity relative to the bore area and use bullets of nearly the same range of SD. Therefore, they'll use similar powders.
However, some of the mechanical stresses on the bullet will be greater for the smaller caliber. Personally, I'd look further into boatanchor's arguments here and follow up some of the leads he's given. Several have gone down this path; pick their brains.
some of the new slow burning powders like RL25, Retumbo, VVN170, H1000 etc... problem is that MOST of the time your pressures are fairly high by the time you reach the GOAL.
Ken Howell's approach might have its best chance with the longer stick powders. These don't have such a regressive shape and can get by with less deterrent. At reduced pressures, the erosive effects of stick powders noted by some shooters of similar cartridges might not be a concern.
I must admit this topic is quite fascinating. I'm a single shot guy who tends to small cartridges. This job is the opposite, and perhaps for that reason it attracts.
