I shoot ICORE and Steel Challenge and I use Blue Bullets 147 with Titegroup, Winchester Brass. I use two different loads but that’s what I prefer. A little softer load for Steel Challenge. I also use at times HP-38. It’s a good powder.
One thing great about rim fire practice is that if you are struggling with weak hand strong hand it great use to work on mechanics and get some confidence. Plus it does not hurt the pocket book as much.