I went looking for this but in 45ACP/Super. I came to the conclusion that I could sabot down to 357, but not to .224.
After learning a little about 3d printers......I think I will print myself some sabots when I get back to someplace I can test.
One day, I shall come back. Yes, I shall come back. Until then, there must be no regrets, no tears, no anxieties. Just go forward in all your beliefs and prove to me that I am not mistaken in mine.