$3000 or less, and competitive at 600 meters. What should I get?

[Chronos]

I'm surprised no one recommended the Sako 75. Guaranteed < 1MOA out of the box (but most good shooters achieve 1/2 to 3/4 MOA), and it's customizable by any handy gunsmith.

As for the cartridge, see this link:
http://www.6mmbr.com/gunweek064.html

 

[GunBoy]

My recommended you to stay with rem700, easy to get accessory, stock, trigger, base or ring, the moment you go to extreme or specialize, you going to pay more, and there isn't any wrong with rem700, it is one of the best to work on, I own up to 5 rem700 in 223, 308, 300 winmag, 300rum, the all work great, not yet fail me yet!

 

[JoeP's old business account]

I would go with the new model 12 low pro or 12 long range (my favorite).

They have a fast twist (1-9 twist so you can shoot heavier .22 cal bullets in .223) 26" extra heavy barrel.

The long range uses the HS Precision stock - a proven performer....

You can also upgrade the unit in the future if like!

The Remington XR 100 is another nice single shot rifle at a vary reasonable price...

 

[6mm Shooter]

Joe have you heard of anyone getting the longrange yet. I have had one on order since savage released tham and I have not heard anything.