Have a Tikka .270 stainless synthetic

[msaucer]

barrel has been bedded, trigger job, answer muzzle brake. Shoots better than moa at 100 yds. with 140 gr. Hornady factory ammo. Would this rig be a candidate for up to 700 yards with the right scope or should I start from scratch for a long range rig?

Depends on what you are shooting. I have almost the same rifle. I use mine on deer up to the 700y range with 140g SST handloads. You need to shoot paper up to the range you want to see what it/you can realy do. The 140g SST with a MV of 3050 will have just over 1000 ft-lbs at 700y.