Before i tightened mine it would place 2 shots close to one another and then one would fly off maybe 2 - 3 inches in a random direction, from the bench. It was never just all over the place but 3-4 out of every 10 shots would go way off the main group. Since tightening i can place 10 shots within 1cm of each other off the bench, consistently.
As far as i know...fliers/bad groups can be one of four things
1 - Barrel twisted in the upper...major warranty repair
2 - Damaged Crown.................major warranty repair
3 - Loose barrel nut.................$20 tool
4 - Loose nut behind the barrel........training , training, training.

Hope you get it sorted.