It's been a long time since I loaded for a G22, but I had no troubles with it. It wasn't accurate enough to suit me but it ran 100%.
What I DO recall about the .40 is that if the bullet sets back in feeding, pressure goes up rapidly, and it does not take a lot of setback to cause significant pressure rise.
Dave Scovil of Handloader discussed this topic, and while he was interested in the accuracy of .45 Colt loads, the same lesson applies I think to autoloaders. You want a tight fit of bullet to case, and the expander plug should be at least .005" smaller than the bullet diameter, AND firmly taper crimp. When you are done, you should be able to press the cartridge firmly against a solid object, bullet first, and the cartridge OAL should not change more than a couple thousandths.
Possibly the OP had some setback, combined with less than optimum cases, and less than optimum case support.
