Re: long range shooting w/.243?
Small animals such as Coyote have been killed beyond 1,000 yards with a 243 win. Especially when using a high bc bullet such as a berger, amax, or smk. I personally have shot targets accurately out to 1100 yards with my SPS Varmit.
Shooting Big game such as deer and antelope with a 243 would probably have a 750-800 yard limit, just because the bullet is not carrying much energy anymore.
I would give the 105 Amax's a try, they are a great bullet. They are accurate and easy to get to shoot out of almost any gun you put them in.
Here's my load for my 243 win:
CCI 250 Primer
Load them just long enough to fit in your mag box, chances are they will shoot
Remington 700 SA 22-243 Win
26" SS Benchmark Barrel 1-8 Twist
Glass Bedded-Grey Bull Precision Stock
Built by Hazer@Bison Barrels in Gillette,WY
Sightron SIII 6.5-24X50MM LRMOA