I have used 52, 55, and 69 grain bullets.

The 55 did not provide good results at all, but the 69 and 52 grain bullets are some very good loads, with the 69 grainers providing a bit tighter group. I still have a little over 200 52 grain bullets left that I will load up and shoot on less windy days. Both ended up liking a charge of Varget over the 2 other powders I tested with.