You are going to be real close to 2600 fps with the Federal Gold Medal 168 SMK load and your 20" Savage.
You need to measure your scope height (center of bore to center of scope. Should be about 1.5" with a 40mm OB.
You need to know your ballistic coefficent for 168 SMK
.462 @ 2600 fps and above
.447 between 2600 and 2100 fps
.424 between 2100 and 1600 fps
.405 @ 1600 fps and below
It looks like drag is DECREASED as the bullet slows, I would punch in .447 as my BC and play with that for a while.
Your bullet weight is 168 grains.
You also need your zero range
Put it into this
Ballistics CalculatorThe cool thing about that calculator is that you can figure drop in MOA, forget about figuring drop in inches and distance, it will drive you crazy.
This will keep you on paper to at least 600yards and then you may need to adjust due to some errors of FPS, scope height and BC.
You need to get someone to let you shoot the sky screens off of their chronograph to get your true MV. Good luck.