Ok, again I preface with Luepy is king around here......but.....

Let me ask this question.  Given the same rifle, same loads, same shooter.  Is one particular brand of scope more accurate than another?  Recognizing that clarity/anti-fog and other scope features have alot of impact on this, but let's talk on the bench, at the range, ideal conditions.  Of course, as everyone knows, realworld shots on game in the field are rarely if ever ideal.

you are getting into paralax and shift issues...

an adjustable paralax scope will be more accurate than a scope that is pre-set at the factory, if you are shooting at a range other than the pre-set (depending on specifics, most pre-sets are 150-200 yards or so).

shift is when you turn the power ring up, the scope actually isn't looking precisely where it was at the other power setting.

the short answer is yes, a scope can be directly related to accuracy, and it is sometimes why a shooter will claim that putting a zeiss/leupold/whateverexpensive improved the rifle's accuracy... (when in reality, it did nothing for the rifle's accuracy, but now the scope is looking at the same spot for every shot).

so then, it follows that a scope can be held resposnsible for some degree of accuracy. the lower end scopes have pretty serious issues w/ shift. eg, have you ever sighted in from the bench at 9x, and then came back later to get a little practice in at 3x and wound up twisting knobs??

all scopes have troubles w/ paralax. the adj obj scopes were supposed to be an answer for this, but many lower end scopes have a hard time truly adjusting paralax, so an adj paralax isn't necessarily the answer.

ok, your specific question... get a nightforce or us optics, and all your scope questions will be answered in regards to clarity, tracking, paralax, repeatability, shift, etc... in hunting applications, those scopes aren't ideal, so everything becomes a compromise. weight, price, eye relief, glass quality, etc etc etc. so, ya pick your compromise.

leupold, zeiss, nikon, etc have scopes that minimize as much as possible the 'bad' variables and still offer excellent optical qualities.

Dakotasin has it about right.  I's just add that within any manufacturers scope model, there are some that are better than others.  Two identical models may have different mechanical issues, erector tubes are a typically difficult thing to get right.  So one may have wild swings on power changes and an identical model may appear perfect.  This happens even with top line scopes, but more frequent with the lower line of scopes.  I had a friend that had a real cheap, usually junk, brand of scope......it was really very good.  but I'll bet it was the 1 in 1000.

BEAR

Totally agree with Dakota.You can through in a Swarvoski and Zeiss for good measure.

God help your bank balance though.

Macca