Originally Posted by gotm4
Yes, but it's not only barrel length. It's barrel length along with gas port location (length of gas system). Take 2 barrels both 16" barrels, one middy, one carbine. If both are quality barrels the middy will have less gas port erosion and be more inherently reliable running at lower pressures and have a longer service life, yet both are 16" barrels. It's the heat and high gas pressures that are eroding the gas ports, get the port further from the chamber and the erosion and cyclic rate are reduced allowing for better reliability and longer service life.