Typically what I've seen is when people replace their HG with certain aftermarket quad rails the top rail interrupts the harmonics of the barrel which can create FTE's. This has been proven by many reputable vendors here. I don't think that in removing the fore end you are going to need to T.I.G. weld it in order to re-create the "back pressure" from the stock fore end. Regarding the vent hole you T.I.G. welded I have a question. I assume that you realize this platform was designed to work with high powered, combat loads correct? So that vent hole would do what it's supposed to do and vent off
