... then you will know what the shorter barrel is about. That extra few inches of barrel puts a fair bit of weight at the end of a long lever. As the name tactical implies, some shooting in competition will be from the standing shooting position.
Some matches do involve position shooting. Balance can certainly be an issue in hand held shooting.
I have read that a shorter thick barrel is accurate in that it doesn't whip around as much as a longer, thinner barrel might. You loose speed with the short barrel which will only become an issue if you are shooting in the wind for group and accuracy. ie. hitting bulls at 500 metres.
A shorter thicker barrel may group better than a longer one. May. Greater variation will likely be seen from barrel to barrrel regardless of length. It would be interesting to take a number of barrels, shoot them enough to establish their grouping capabilities, then progressively shorten them and see if grouping ability increases as the barrels become shorter. This would be a very costly, time consuming experiement.
A faster bullet spends less time in the wind and is therefore less affected. Of course your bullet choice can affect this so look for one with a high ballistic coefficient. High speed plus high BC = accuracy in the wind.
Velocity and bullet performance are certainly issues when it comes to reduced wind drift. A more efficient combination will result save points.
I have the same gun and it shoots very good groups. It is less able as distance increases when the wind comes into play.
cheers