Okay I have a VERY good machinist friend and I want to port the slide and barrel on my walther p99c in .40. What all do I need to tell him to do? I figured get it set up like I want and have him drill through the slide, insert and mark the barrel, and have him drill through the top of the barrel. Use an end mill and smooth it out and then check the barrel and have it refinished. Is there any particular angle that helps with the porting versus just a straight 9o* angle? I am not a machinist so I am just trying to figure out what to tell him to do :whistling:.