Hi Micky,
That’s at least two then, so maybe there were more rifled barrels fitted to the 7th Series Titan than we might have imagined. Being rifled would have precluded the use of steel darts for fear of damaging the rifling so one can understand why smoothbore would have been preferred for this class of air pistol. Anyway in my experience, the difference in accuracy between smoothbore and rifled barrels at their intended range of 6 - 10 yds is minimal to say the least.
Brian