It does seem to work better if I get all of the fouling off of the front of the cylinder with a lead cloth.
Kieth,
I may need some help with this, I dont even know where a "shim" is supposed to go. Hell I cant even shoot a stage clean anymore... That Glock in my hand felt pretty good during that classifier on Tuesday. It may be time for an intervention, I keep having nightmares of steel not falling.