I'm also using lil-gun,
I've tried my RFD's favoured load which is 11gns under a 35gn V-max, but for me it was quite poor grouping, 11.5gns gave tighter groups so I've just spent the afternoon loading up a few more at that, along with 11.8, 12 & 12.2 to see how they go through my HW60.
Interestingly there was only 20fps difference between 11gn & 11.5gn, 2723fps v 2743fps ave.
Has anyone else got Velocity readings to go with the loads?
be interesting to see if the favoured loads in different rifles equate to a common velocity range.