A few years ago I discovered some problems with my handgun shooting technique and developed my own "Crossed Thumbs" grip, which has served me really well.
I had used a thumb forward grip all my life, and had never been a very good pistol shot - with one exception. That was with an Baby Erma Luger. For some reason I could shoot it really well. I was quite a good shot with a rifle, and it bugged me that I could not transfer that skill to a pistol.
One problem I discovered was that the gun deflected slightly when I pulled the trigger. Countless hours were spent in my bedroom with a BB pistol and later with an Airsoft 1911 trying to eliminate the deflection. What I determined was that when pulling the trigger, all the muscles in my right hand would move slightly. The more tightly I gripped the gun, the worse the deflection was. The only way to eliminate it was to completely relax the muscles in my right hand. Well, having a completely relaxed grip with a 45, you lose control pretty quickly. Remember the Baby Erma Luger? I was able to shoot it with a relaxed grip because of the unique weight distribution of the Luger.
I had a marksmanship instructor work with me a while, and he mainly worked on my stance and relaxing my shoulders, etc. It helped but I still could not achieve the level of marksmanship I expected. And I still had that annoying deflection when I pulled the trigger. The only thing I could do was compensate for it with a little Kentucky Windage.
I analysed photos and videos of expert pistol shooters trying to figure out how they eliminated this problem. The crossed thumb grip stood out. It did not look natural to me, but I decided to try it.
With my grip, the muscles of the strong hand are used for one purpose only: pulling the trigger. The weak hand's muscles do everything else. The trigger guard rests on the weak hand index finger, which supports the weight of the gun. The weak hand also cinches the strong hand into place around the grip allowing the strong hand's muscles to relax.
I was able to successfully adapt this grip to every type of handgun with just minor adjustments - semi-autos, double action revolvers, single action revolvers, and even an Encore single shot.
I still shoot with that marksmanship instructor occasionally. He's amazed at how well he taught me (we'll just let him believe that...)
