Proof Research pre-fit Carbon Fiber barrels for Zermatt Arms actions offer several advantages over traditional steel barrels. The obvious advantage is that these barrels are up to 64% lighter than traditional steel barrels of similar contour. Improved heat dissipation is another huge selling point. Cooler barrels means longer lasting barrels. One of the other key features is unprecedented Durability. Proof Research Barrels are wrapped with high strength aerospace-grade carbon fiber which is impregnated with a proprietary matrix resin.