Ruger AR-556 MPR in 450 Bushmaster

Image courtesy Wikipedia

For anyone who's not familiar with the 450 Bushmaster, here'a comparison with the standard .223 round. Think of it as a 45-70 for the AR platform. You're not going to achieve the same MOA as with more streamlined projectiles but when you're making holes as big as dinner plates that probably doesn't matter so much. A formidable round in a proven platform built by Ruger, this is one to bucket list.

• Lower receiver is fitted with Magpul® MOE® grip and MOE SL™ collapsible buttstock on the Mil-Spec buffer tube.
  
• Handguard is free-floating for accuracy and the slim, 15" length provides enhanced ergonomics and support.
  
• Made from aerospace-grade 7075-T6 aluminum forging, the flattop upper receiver includes a forward assist, dust cover and brass deflector, and is Type III hard coat anodized for maximum durability.
  
• Bolt is machined, shot peened and pressure (proof) tested to ensure strength, structural integrity and durability.
  
• The Ruger® Elite 452™ AR-Trigger is a two-stage trigger that offers a smooth, crisp, 4.5 pound trigger pull. It features a full-strength hammer spring for consistent primer ignition and a lightweight hammer that enables a 30% faster lock time over standard MSR triggers.
  
• Magpul® M-LOK® accessory attachment slots along the 3:00, 6:00 and 9:00 positions with additional slots on the angled faces near the muzzle.
  
• Cold hammer-forged 4140 chrome-moly steel barrel with ultra-precise rifling provides exceptional accuracy, longevity and easy cleaning.
  
• Chrome-plated bolt carrier inside diameter and chrome-plated gas key inside diameter provide exceptional resistance to hot gases. The gas key is staked so that it will not loosen after extensive firing. A matte black oxide finish on the exterior of the bolt carrier provides corrosion resistance.
  
• Ruger® muzzle brake is a radial port design that significantly reduces felt recoil and muzzle movement. The threaded barrel allows for standard muzzle accessories to be installed.
  
• Also includes: One Magazine