The original M16 was designed with a relatively thin and light barrel, now generally referred to as a "pencil" profile. While this provided a very lightweight and balanced rifle to carry, it has a potentially very significant issue - zero shift under heat.
As a result of that issue, and a few others like barrel flex while under slings strain, we've seen M16/AR15 barrel profiles grow increasingly thicker and heavier over time. This generally solve the problem however it moves away from the original design goals of the lightweight carbine that the AR was intended to be.
Modern barrel manufacturing techniques have potentially made the pencil profile once again viable, and we are using Faxon pencil barrels in our WWSD builds.
So the questions we're asking in this video are:
Did the original Ar15/M16 barrel truly have this problem? Do modern manufacturing techniques alleviate it sufficiently well that the pencil barrel is again viable in 2017?
Here's a link to Faxon's barrels: http://faxonfirearms.com/barrels/
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