Chuck hit the nail on it's head. Twist does not determine a barrels accuracy. I have accurate 1 in 66 barrels,1 in 36, 1 in 32, 1 in 28 and 1 in 24. The slow twists like 1 in 66 stabilize short projectiles ( short in relation to diameter) such as round balls. Longer projectiles require faster twist rates.
The key is matching projectile to twist rate. Turn in 28 is the most prevalent twist rate in todays inlines.
Virtually all elongated projectiles in common use today will be stabilized in a 1 in 24 to 1 in 28 twist. Any barrel in this twist range has the potential for accuracy.
Many factors affect accuracy. Accuracy can only be determined by shooting. There is no magic number or formula that will guarantee an accurate barrel.