To get good at longrange shooting you need to shoot at long range-alot!
That seems obvious and self evident. It is, and you need a gun you can shoot and practice with- alot
I would suggest picking a rifle that won't beat you up and that you can practice alot with. That way you can gain experience with reading the conditions(wind drift) and work on your technique as well.
Alot of guys buy a big boomer for longrange shooting and then find it wears them out and is very expensive to feed. So they don't shoot enough.
When I only had access to a 100yd range I shot a .22 and .17HMR alot. The 22 drops and drifts alot at 100yds and you will definitly become a better wind doper and refine your technique. It is a good simulation of shooting a big centerfire at long range. But still there is no substitute for the real thing.
I shoot a 6br alot at 600+ yards and it is a pleasure to shoot.
It is easy to load for and is a very accurate round. Practicing with it has made me a much better long range shooter.
That was the best move I made.
Practice with the .22, 17 HMR and 6br and get another rifle for long range hunting that would suit your needs.
Of course I also shoot a 204 ruger, 223rem,6.5 wssm, 270wsm,7wsm, 300win, and to make matters worse I am having a custom 338 Lapua built.
I like the 7WSM for a good all around cartridge. If you wanted to get something mainly for elk get something bigger, like a 338 you could go with the 338 edge or Lapua. If price is no object, the Lapua brass is better, but a quite a bit more costly.
If I was going to buy just one gun I would buy a 7WSM and put a break on it and practice and hunt with it until I wore the barrel out. You can shoot 168, 180 gr Berger VLD's, 162AMAX, or 175 SMK's and shoot to 1000+yds. with ease.
I have one and have had great luck with the 168 vld's.
You need a good setup for longrange shooting and buying a rifle that is setup by a good gunsmith is not cheating. It's smart!!
When I say smart, I mean very smart! You will know that your rifle will do it's job, the rest is up to you.
If you have the money there is nothing nicer then getting your hands on a fully custom rifle
setup EXACTLY the way you want it.
You will save yourself alot of time and effort and be able to concentrate on shooting.
Price was an object to me so my first few rifles were Savages that I had bedded and they are awesome shooters. They can shoot 1/2" or better 5 shot groups very consistenly. Of course I do have to pull the trigger.
Hope this helps .