A must have for your Ruger 10/22 .22LR rifle.... this incredibly accurate MagnumLite graphite barrel is a Magnum Research exclusive. The patented uni-directional graphite carbon fiber construction dissipates heat so the barrel stays up to 43% cooler than steel barrels in a standard 500-round/20 minute test with no change in zero. At 13.04 ounces in .22LR it's 75% lighter than a conventional steel bull barrel. This barrel has a twist rate of 1 in 16 and total length is 17-inches. The patented uni-directional graphite carbon fiber construction dissipates heat so the barrel stays up to 43% cooler than steel barrels in a standard 500-round/20 minute test with no change in zero.