I am doing some work on my 210 barrelled upper. The barrel appears to have had the gas port hole drilled completely through both sides of the barrel, with the lower hole plugged and the upper hole plugged then drilled out to the correct diameter for the gas system.
Just wondering if this is an accurate description of how it is done? I had always assumed the gas port hole was simply drilled through the upper portion of the barrel until the bit entered the bore then stopped.
Also curious, from a former manufacturer standpoint, how it's plugged and with what material?
Hope you can answer these questions for "inquiring minds".