Re: Trying to go the distance with a .243
You didn't state your load or what scope you have mounted on your baby. How does she shoot at 100 yards? It has to be very good at 100 to hit anything at 600. You may know that but thought I would mention it. You may also run out of adjustment on your scope trying to zero at 600 yards. You may not, but be aware that it could happen, in which case you would need a base with built in elevation, or a different scope with more adjustment or a ballistic reticle.
Good luck, have fun and be safe.