I cut my 20" barrel to 16"... The gas port is now 3.25" inches from the muzzle (I already ordered a 20" Varmint for the replacement, incase this goes horribly wrong.) Now, I need to know what are the sizes you all may have heard the gas port needs to be opened up to (I've heard 0.05 to .110), and, what are the spring changes that need to be done if any. I know you guys know this. Thanks all !!!