x3 on above
I would bed the action to the factory one and start killin stuff.
if you do want to kill stuff way out there it will take lots of practice, if you're practicing with TTSX's its gonna be very spendy.
what I did with my 300wm was to hunt with 180 accubonds, and practice with 180 BT's. they shoot the same in my rifle out to 600 yards, the BT's are a little cheaper to shoot too.
I would start with reloder22 powder, check a manual or go here
http://stevespages.com/308_7.html for an idea where to start, start with a light load and work up.