I can't say with any experience but I am going through your same deal right now. I have the .17 hornet and all components and I will be reloading shortly. The factory ammo shoots so well that primarily I am interested in 25 grain'ers. My biggest challenge was finding suitable powders. What I settld on, and what I found, was AA2200. Looks just about perfect for 25 grain pills. I have heard that 1680 is great but it can cause some pressure issues. I also have a pound of 4227 that might work ok. I will let you know what I come out with. I am curious if I willl see the dreaded shift in performace from new brass and fire brass. I've never worked with such a small round before.