п***жь и провокация!
Дядюшка Стоунер говорил, что ничего путного из этого не выйдет и практика доказала. Гуглите источники.

Over Stoner's objections, various experimental composite and 'Sullaloy' aluminum barrels were fitted to some AR-10 prototypes by ArmaLite's president, George Sullivan. The Sullaloy barrel was made entirely of heat-treated aluminum, while the composite barrels used aluminum extruded over a thin stainless steel liner.