I have to weigh in on this.
Now, keep in mind that I don't buy into a lone sniper prepper/survivalist mentality. But I do know about building a rifle.
As a sside note, look up greybull precision. Ive worked with Adam for a long time. Their success comes from using a quality rifle, with great glass and their custom turret ranging system..
You want to start out with a good solid action. Remington 700's are popular because they are easy to blueprint. Meaning they are easy to turn on a lathe and remove as much out of tolerance material as possible.
You want a stiff receiver, making a savage 110 sub par. Your lugs should be smoked and lapped before a barrel is installed and you want your barrel headspaced correctly before it is installed. No pull through reamers.
you want your barrel lapped and polished correctly.
you want a freefloating barrel with a .30 clearance minimum between the stock and the barrel.
You want length of pull and grip size customized for the shooter
You need to know what round you will be using in the rifle. No mixing and matching.
muzzle crown should be a 11 degree recessed crown
barrel contour should be a minimum of a #4 up to no contour.
scope mounts should never be quick disconnects. A scope needs to stay on the rifle. If you take it off, automatically assume you will have to re-zero the weapon.
triggers should be set to the shooters preference using either a neutral or preferablly positive sear engagement. Never negative. No accutriggers. They move, adjustments are never standardized. One place youshould consider spending money on is a giessele trigger or a timney. They're worth themoney,if only to prevent the headaches.
My personal favorites are Winchester 70's, rem 700s, cz500, a cheaper alternative is a howa 1500. It's a clone of the 700. Older savages are good guns too. Just no spring adjusted triggers.
glass is a preference, just remember thatcheep glass has bad parallax problems and it will cause misses at distances outside of 400 yards. Leupolds are great, nikons are good for the price. You can spend a grip of money on glass.
Barrel manufacturers is a huge consideration. The better the barrel you buy, the better the end product will be.
you want barrel length and twist rate in consideration so you will know the proper barrel length