I purchased my first Glock, a model 22, exactly one week ago today. I took it to the range the day after the purchase following a field strip and lube in accordance with the manual. I fired exactly 100 rounds of Winchester white box target ammo through it without a single failure. The gun appeared to be perfect until I field stripped it again to clean and lube once more. When I attempted to reassemble it the slide would only go so far onto the frame. It stopped abruptly approximately 1/8 inch from the back of the frame. The only way I can get the slide to properly install on the frame is to first move the trigger slightly forward with my finger. That allows the slide to proceed rearward such that the trigger will reset and normal operation is restored. The gun operates normally in all respects with the exception of the above problem during reassembly. Each time the gun is field stripped the above problem resurfaces. Has anyone else experienced this condition, and if so, did it require returning the pistol to Glock for correction?