The seating dies are nice, but I haven't seen a lot of change in groups from changing seating depth. What interests me is a Lee collet neck sizing die for 7-30. I use one for .223, .243, and .220 Swift. They do seem to give better groups. While Lee does not make one for 7-30, they will do a custom if you send in 5 pieces of fired brass and $60 (??). If you want to experiment, contact them, buy one and let us know if they work.
I use the 7-30 for hunting and while I would like some more accuracy, it works as is. If someone else tries it, I may spend the money.
thanks
mike