I've kept the dwell on mine at 14 ad so far I've had no problems at all, that was with a low rise. so try it for a while and see how you get on.
I've seen a bolt on the AOG home page that is supposed to cause backspin to increase accuracy and distance, speaking to people the've all made good comments about what they think, but as of yet I don't know anyone who has one, so I don't really know what they are really like
sorry if I've not been much help.
Bif