I don' t know what to say for sure. I have had many contender barrels and all shot groups equal to most rifles of the same caliber. They are however much harder to shoot well. Any movement as you fire will translate into drastic misses. If the scopoes are mounted good and tight and you have a good rest you should be able to fire good groups. I would doubt that any fault would be with the barrels. At least I have never found an inferior TC product. Check your mounting again and start your shooting at 25 yards. Either scope you mentioned should be fine.