It turned out to be the barrel, not the bolt carrier group.
The Dracos "StraightJacket"composite barrel from Falkor Defence keeps the inner barrel cool by rapidly dispersing the heat to the exterior, preventing the barrel from flexing to keep shots on target in rapid succession. Not only this, but the adjustable gas block adheres to the true Dwell Time of a barrel's length at the point of which the bullet actually leaves the barrel, be that extended with a suppressor or not, to keep shot groups tight by extending the length of the gas system virtually.
This was around eight years ago, but just as recent as last year there was a different system from TacomHQ with their "Structured Barrel" design, which relies on the Axial Compressor principle with eight hole I-beam structure to reinforce the main chamber, thus allowing for 300% more surface area for heat dissipation, along with external detailing which behaves as a heatsink as heat travels to the tip of a material.
