DoubleF;
The sight notch on the hammer is wholly inadequate, but it can be improved with judicious filing. I use a small round file and I put extra pressure in the direction I want the ball to impact. It both lowers the notch, and slightly opens it up for a better picture. When I'm done, I have a "U" shaped sight, rather than a "V" shaped sight and it will be a little off center in the direction you want your balls to hit.
Dan C