Olympic Arms' flagship accuracy build — hand-fitted Ultramatch upper and lower, Kreiger or Lothar-Walther barrel, free-float handguard, and a Jewell two-stage match trigger. Built for National Match competition, the UM-1 represented Olympic Arms' highest quality offering. Type: Rifle Action: Semi-Automatic Caliber: 5.56x45mm NATO Capacity: 30 Year introduced: 1995, United States Weight: 128 oz Overall length: 39.5" Status: Discontinued Intended use: Competition, Target Shooting