Tom, how deeply do you go into the barrel with the cone re-cut? Reason I ask is that it seems to me that to totally eliminate the restriction you'd have to run it the whole distance the barrel resides within the cylinder frame, because as I understand it, as much of the barrel length that's in the cylinder frame, ( 5/8" on my S&W 640, 7/8" on my 629), that's how long the constriction is. Am I wrong here? Help me understand, please. Thanx, jd45