Is it shooting low when you pattern it or is it a perception you have when you miss a flying target? I ask this because most people I have observed patterning a shotgun shoot low. I think this is for one of two reasons. Wingshooting is a reflexive act, but patterning is like shooting a rifle to some extent. Most people in that situation tend to put an open rifle sight at the bottom of a bull and shoot. If you do this with a shotgun on patterning paper, you can shoot a foot low or more. Try putting a 4" dot in the middle annd cover this up with the bead.

Another issue is simple flinching. Flinching is not always fear of recoil; it can be anticipation of the shot. I don't know the number of people I have seen over many years who are not familiar with a gun and don't realize the automatic safety has engaged. When they try to shoot, you see them try to pull the trigger and nothing happens except they lunge forward into the gun and the muzzle drops downward. People seldom shoot rifles from a standing position anymore, or you would see the same thing. With shotguns, they are always standing, and it is easily apparent what is happening. These same people have no problem shooting at moving targets.

I have owned a bunch of Browning O/U's and I never owned one that shot low. Unless you have a really weird shoulder, pitch would be the last thing I would think to tinker with. I like straighter stocks, but don't have trouble adjusting to comb heighth if I have too. The real payoff for me is to have the cast right, and even a little more at bottom than top. If you are shooting low at flying targets, try the comb risers. If it is with patterning, pattern the gun using a low gun stance, then shoot in with smooth motion using a mount, point, shoot technique and use a center dot. You may find a big difference.