Thanks, I did locate the part you referred to and yes I had not installed correctly, but after rectifying that it still would not latch. I have removed the safety to check but that did not alter anything. The longbow does not use a rod to cock the trigger but uses a notch in the piston. It seems as though the piston travels so far back and starts to slip over the sear but then fails to activate a secondary sear which is the part you mentioned in your previous post. I am going to bite the bullet and strip the trigger to inspect the sears.