231 works just rigt in my 52 at about 3.0 gr but each gun is an individual and a little bit of experimenting is probably in order.

I don't want to resurrect the "mixed brass vs sorting-by-headstamp" debate but my experience is that sorting and/or being selective in brand of brass used will minimize some of those mysterious fliers that spoil an otherwise perfect group.
You can definitely feel the difference in neck tension when seating the bullet and I can't help but this believe this can have an effect on consistency.