That's what happens when the screw hits the stream.
To answer you first question, No. If you have to shorten the stream that much, you need a smaller head in those spots, not PGP's.
Low angle nozzles will drop the height of the stream, not so much the radius.
What is the coverage distance that you are looking for? Do you know what your head pressure is? Depending on the pressure that you are working with, your distances will be from 22' to 50'. If you require a shorter coverage area, you will have to install a smaller (shorter distance) head.