I've been working with a .22 Mag. barrel for my CZ 455. Overall, it shoots best with the Hornady 30gr. VMax loads. As luck would have it, it's often on sale from various online vendors, for around $11/box. It's usually the least expensive ammo around.
This barrel doesn't much like the 40gr. loads from ANYONE, it's just not a great barrel. I've shot CCI, Winchester, Fiocchi, and maybe another or two. Whatever I can find. Again, it seemed to like the Hornady 30s best, which suits me pretty well, since I bought it to use on prairie dogs, if I can get back out West sometime.
I've tried the Federal 50gr. loads, and it did not excite me, it was crap in this rifle. I've got a fair stockpile of the Hornadys, when they're gone, I think the barrel will go bye-bye, too.
I like the .17 HMR more better.