I've got a very nice S&W 5906 that I'm enjoying however its got a strange problem. When the gun is cocked the drawbar is not fully moving or something because when the trigger is pressed a small amount there is resistance, a click, and then moves somewhat upward and the trigger is able to move back to fire the gun. This only happens if the user keeps his finger off the trigger while the gun is being cocked or if the hammer if force ably pulled back. I've shot oil at ti but the issue persist, any thoughts on how to get it to quit?