What kind of mods have you done to your rifle so far, if any?
Is it a factory barrel/action/trigger? Has it been bedded? Some more info would help on getting back positive responses.
I am not trying to be a smartass, but I feel the need to correct your question:
I am curious if there is a factory loaded round that I can purchase that has consistant BC ( balistic coeficient) out of the box.
BC is determined by the bullet
itself, and how well it flies through the air. Higher BC = less drag during flight. The brand of ammo really has no effect on consistant BC (assuming they are using quality bullets). ES and SD are another story however. Different ammo will produce better or worse Extreme Spread & Standard Deviation which will affect your ability to hit a target at long distance. If the velocity
(which is what ES and SD are indicating) varies shot to shot by too much, then the impact on target will vary shot to shot too.
Once again not trying to put you down, just tryin to let you know the terminology.
Good Luck 2U.