The nodes will be in the usual places--as a rule--but we allow for exceptions, always... so we work up from starting charges.
Check
www.hodgdon.com for load data for the .308 and 168's... the Bergers will not be that different as to their max charges as other 168's Hodgdon shows data for. The following charges are well within Hodgdon's parameters for the 168's they show...
In Winchester brass... the node with IMR 4895 should be at 43.6 grains, but you'd want to check 41, 41.5, 42, 42.5, and 43 grains just to be safe. You don't have to shoot but one shot at each of those charges...
With 4064... it's going to be just north of 44 grains... work up from 42 grains. Probably it'll be at 44.4 grains or somewhere in there.
With Varget, it'll be about the same as 4064, but work up from 42... Varget has a high node close to 46 grains but I have never gone there with the Berger, so I can't advise as to that.
The old standby, 39 grains of IMR 3031 is a safe and accurate load for most 168's in Winchester brass for the .308...
I don't know how sensitive you'll find these bullets to be to seating depth... if you're shooting a Remington action, you'll have to load them to 2.800" or they won't mag feed... and you won't want to go much shorter than 2.785" or so I wouldn't think.
Dan