Pertaining to the original thread, I use 165gr .308 accubonds with great success. They are the most accurate bullet out to 200m by a large margin out of my tikka t3x.
Weight is normally a non-issue unless you're planning on hiking many miles a day with the rifle. The magnification rule of thumb is: 1x per 100 yards. So if you're only hunting at 400 yards, a 4x scope should do the trick. That being said, my eyes are not the greatest. I've found 2x per 100...
For your distance needs, I would go with the 2.5x10. The wider fov at 2.5 will be nice to get on target, and you'll still have 10x on the high end to positively ID at your engagement distance. Can't really go wrong with either though!
Protein: Optimum nutrition whey. Pre: Jaked factory nitro surge. Creatine: Bulk supplements on amazon. That's really all you need to succeed, my friend.