Originally Posted by
HJB
Maybe I'm missing something, but why isn't it as simple to shoot the gun using a rest of some kind for your hand and see if the shots are still to the left. I always do that when I first shoot a new gun or replace sights on a gun. I like to know that the gun is "sighted" properly, or if not, and I can't adjust the sights at that point in time, I will at least have some idea where to hold to make the best shots.
Why would that not be better than having some "known good Glock shooter" or anything else to determine why you are shooting left ?