Buffalo Bullets just went out of business, then I just read on this forum I believe, where they started back up again. I suspect that you will have trouble finding them in a year or so, so why work up a load if you can't get them in the future? I agree with Cayugad use a sabot, that is what the inline was designed for and therefore will shoot the best with. XTP are excellent as Cayugad recommended.
Chap Gleason