02-10-2015, 12:01 AM
LRRPF52 is right on the mark. I will draw a center line from the center of the barrel gas port to the barrel shoulder with a fine pencil using a straight edge. I will do the same with the gas block and mark the center of the gas block face compared to the center of the gas block port.The gas block port is always bigger than the barrel port and I will be able to see how much adjustment I use for the gas tube and still have aligned port holes. I will then use the right feeler gauge width to snug the gas block face to the barrel shoulder for an exact fit if needed. When the marks are aligned I will tighten just enough for a good hold so I can check my gas tube to gas key fit and adjust if needed. When all is good I will then tighten the gas block screws with red loctite. When all is good I can erase the pencil marks.