I always used 55grn bullets in mine as they were far easier to come by. I can't remember the weight of the bullet (60grn ?) but Sierra manufacture a heavier bullet that is specifically made to suit .222rem.
I had superb results using TU2000 and Varget powders both no longer available, and also with Vhitavuori N130.
Good to know, it'll be n133 il be using. The lad says he was using 60 something grain bullets in his 222 and that accuracy was not great, which I was not surprised about as it seemed a tad heavy for 222, or at least that's what I thought.
Cheers
Ali