M16 Upper Receiver Groups now available from Colt! These 20” Upper Receiver Groups feature the same barrel used on M16A2 and M16A4 rifles, which has a Government profile and feature a chrome lined bore and chamber, along with a 1-7 twist. Colt has paired these with Magpul MOE handguards to make them fully modular. Available with or without a charging handle, bolt carrier group, and back up sights.
Big Book Catalog, Issue:73, Page:003