Re: Questions regarding scope/rifle combo
Welcome USMC30. As I am not one of the most experienced members on this site, I will try to start things off in the right direction for you, but I am sure you will get some great advice from some of the senior members shortly. Since you already have the rifle and caliber purchased, all I will say here is that your friend didn't lead you astray. I have owned 2 Savage rifles up to this point as well as Remingtons, Winchesters, Rugers, Sakos, Brownings etc. and in my experience the 2 Savages have been one, two, for the most accurate out of the box rifles I have ever owned. They haven't been the best quality, but for long range work, in my opinion, accuracy is more important than all other aspects. The 308 seems to be the go to caliber for the beginner. Cheap to shoot, accurate, lots of ammo info and choices. It will get you out to 1000 yards but by the time it gets there it will be all out of gas. What I mean is that the 308 is fine for paper but as far as hunting goes, know the calibers limitations. Being that you didn't mention hunting, I would say, good to go.
A lot of long range equipment is personal preference, quality wise one brand may be just as good as another but it is up to what you prefer, that makes it right for you. So for me the scope that you have, although in the upper end of quality, is what I would call over gunned. I come from a Rocky Mountain hunting back ground and for that a 3-9x42 was the standard, so just take this with a grain of salt. If I had come from a target shooting back ground I would be more familiar with the extra magnification, but I never seem to zoom more than 10 to 12 power on my scopes, this is just where I am the most comfortable. I must say though that I did love every one of my Leupold scopes that I have ever owned.
As far as what round to use, I have to say, tuned hand loads!!!!!!!!!!! I am probably the biggest advocates of reloading out here. If you don't hand load you will just have to try several different loads in your rifle to see what it likes. I would suggest match grade ammo if you want to be serious, and if that is the route you go it will be expensive. If you do reload then try the Sierra 175 gn Matchkings, or Hornady 168 gn A-Max, I have had good luck with both of these bullets.
Accuracy, well here there are so many variables that there is no telling what you may end up with. I have ended up with as many lemons, as I have found good ones. Just for an example, one of my lemons was a Remington Sendero in a 300wm caliber. Remington is a great brand of rifle. The go to for long range work, but the one I got had so much free bore that I could not get 180 gn bullets anywhere near the lands. This rifle would only shoot 3 inch groups at best. Would I recommend this exact rifle for someone, heck yeah, I just got a lemon. All I can say is that with my Savages, I was getting .25-.75 inch groupings. I would not hesitate to say I would expect a MOA or better shooter.
Bi-pod, my only recommendation here would be a Harris. Again this is a personal choice but I have never had a bad Harris, in my opinion they are tanks. I would suggest the S-BRM 6to9 inch. If you are shooting prone you want to try and stay as low as you can and off of a bench you won't need much height. The swivel, notched legs are the Cadillac model, not needed but since the bi-pod will last so long and be used so much why not get the best. Midway USA has them on say right now for $88.99 well worth the money.
Post some pictures for us of your rig. Once again welcome, and enjoy your new set up.