Traveling without my Glock Armorers Manual. I have a Gen4 M19 and a Gen2 M19. The Gen4 has a much harder and longer pull than the Gen2. Reading the botched polish the parts thread just below here, got me wondering why there was a difference. I have a question on the proper depth of engagement of the trigger bar and the firing pin lug. Looked at from the rear, the Gen4 M19's firing pin lug hides the entire rear surface of the trigger bar that acts as a sear. Roughly flush bottom to bottom. Looked at from the rear, the Gen2 M19's firing pin lug hides just slightly more than half of the rear surface of the trigger bar that acts as a sear. Just less than half is visible under the bottom of the firing pin lug. None of the parts are bent or modified or rounded like in the thread below. Blackening the firing pin lugs front surfaces shows the Gen2 has about 1/2 the engagement of the Gen4, just as you would suspect. The Gen2 M19s parts when engaged look about like the drawing in the thread below. It has fired about 600 rounds recently without the slightest problem. Simple question: How does the Glock Manual describe the proper relationship of the parts when viewed from the rear?