Straight-walled case fans get another option with the new Rock River LAR 450 Bushmaster.

Just a week ago, we reported a new LAR-15 model from Rock River Arms chambered in 350 Legend. Well, straight-walled cartridge case fans get ready, ’cause here comes another one. Rock River just announced the LAR-15M in .450 Bushmaster.

Rock River LAR 450 Bushmaster

The straight-walled case phenomenon, especially in AR designs, provides versatility for gun owners. In states where law allows, rifles chambering straight-walled cartridges provide opportunities afield. In an AR design, the combination happens to double as a wonderful defensive gun, predator control rifle or general interest plinker. From short- to mid-range distances, the .450 Bushmaster variant should prove up to most tasks.

The Rock River LAR-15M .450 Bushmaster delivers 1 MOA at 100 yards, according to Rock River Arms. It features a 16-inch stainless steel cryo-treated barrel. It utilizes smooth rifling with a 1:24 twist and an RRA Operator Brake. A two-stage trigger provides a crisp break, according to Rock River Arms.

The rifle ships with a six-position Operator CAR stock. An overmolded A2 pistol grip and 13-inch free-float handguard come standard. A low-profile gas block and mid-length gas system drive the platform. A full-length top rail and M-LOK system provide lots of options for accessories.

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RRA LAR-15M .450 Bushmaster Specifications

  • Caliber: .450 Bushmaster
  • Lower Receiver: Forged RRA LAR-15M Multi-Caliber Marked
  • Upper Receiver: Forged A4
  • Barrel: 16-Inch Cryo-Treated Stainless, 1:24 Twist, 5/8-32 Thread
  • Muzzle: RRA Operator Brake
  • Gas Block: Low-Profile Gas Block, Mid-Length Gas System
  • Trigger: RRA Two-Stage / RRA Winter Trigger Guard
  • Safety: RRA Standard
  • Handguard: RRA 13-Inch Lightweight Free-Float, M-LOK Compatible
  • Buttstock: RRA Operator CAR Stock
  • Pistol Grip: RRA Overmolded A2 Grip
  • Weight (w/empty magazine): 6.8 pounds
  • Length: 37.5 Inches Extended
  • Accuracy: 1 MOA at 100 Yards
  • Includes: One Magazine, RRA Case, Manual, and RRA Limited Lifetime Warranty
  • MSRP: $1,100

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