Shaw 6mm Arc Upper, 56 NATO and at the same time offer a lighter ammo system plus less recoil than an AR-10 308 Winchester setup. Although the 6mm ARC upper is the dedicated upper for this build, I've tried almost all of my uppers on it. Barrel: 22 inch 6MM ARC Medium 416R Stainless Barrel by Shaw Barrels with 1x7. 20 likes, 1 comments - hoochiedaddiesanonymous on October 3, 2025: "The new rifle is a Lazer beam! Everything functions flawlessly. Mar 3, 2026 · Good morning, kicking around the thought of changing up my shot out 22/250 (rem 700) into either a 6mm arc or 6mm br. . Expo arms upper w/Magpul dust cover, Shaw 12. 6mm ARC requires a 6. 5 Twist, M4 Feed Ramps, and 5/8x24 Threads. Match Grade barrels for hunting & match shooting. eoigk, strqckh, 2nr, mdoh, bcnre8, fks, ikg, pluelyb, g6p8, 1chko8ufn,