Re: Glock grips?
Rubbers make the glock grips huge for me. I've got normal sized hands, maybe slightly small fingers, but basically average. Stick on grips (get the sand, not the rubberized) or stippling with a soldering iron is best.
But I think you're asking more about the biomechanics of a drawstroke than the grips themselves? It sounds like maybe you're swinging up when you draw, rather than punching the gun forward from your center mass.
My draw stroke on any pistol looks like this. You can sort of generalize and say each one of these stages takes a quarter second, plus the quarter second it takes for your brain to react to the stimulus to draw.
1. (fast, big movement) master hand to grip, support hand to center mass.
2. (slow, precise movement) secure grip on pistol with master hand--however long it takes to get a good grip (usually 1/4 second-ish, but maybe longer)
3. (fast, big movement)draw and bring gun to center mass, support hand meets grip, punch both arms forward. This punch forward from your center mass is crucial in terms of allowing your brain to automatically drive the pistol sights to the right place.
As you punch forward, you begin to become aware of the sights in peripheral vision, brain seems to naturally adjust for grip angle.
4. (slow, precise movement) fire shot getting the best sight picture possible for time available. Ie for long range maybe you're getting a perfect sight picture, for short range maybe you're just getting a flash sight picture, maybe just the front sight post on the target, even.
I've found that if you're punching the gun from center mass, your brain automatically adjusts the grip angle because it's aware of the sights as you are pushing the gun forward.
IE, your first stage in picking up a handgun is establishing your master grip. You should have that a full second before you're even fully able to fire a shot.
Finally, what is your support hand doing? If you're shooting weaver, with your support hand wrapped mostly around your master hand, that is going to contribute to the problem you are describing. If you are shooting isocoles, with your support wrist locked all the way down (your support hand thumb parallel to the ground), that tends to make sight alignment problems go away also.