The Ruger AR-556 MPR is a semi-automatic rifle chambered in .350 Legend with a 16.38-inch barrel. It weighs 6.6 lbs. and has an overall length that adjusts from 33.38 to 36.63 inches with its collapsible stock. 
 

Key Specifications 

• Model: Ruger AR-556 MPR 
• Caliber: .350 Legend 
• Barrel Length: 16.38 inches 
• Capacity: 5+1 rounds 
• Weight: 6.6 lbs. 
• Overall Length: Adjustable from 33.38 to 36.63 inches 
• Action Type: Semi-Automatic 
• Finish: Black Type III Hard Coat Anodized 
• Stock Material: Synthetic (Collapsible) 
   

Detailed Features 

The Ruger Elite 452 two-stage trigger is factory-installed and gives a predictable break that benefits accuracy in both hunting and target shooting applications. The free-float handguard uses Magpul M-LOK slots for bipod, light, or grip attachment without affecting barrel harmonics. 
 
The rifle ships optics-ready with no iron sights, accepting most standard AR-pattern rail mounts. The collapsible stock adjusts to fit different shooters. The cold hammer-forged barrel and 7075 T6 aluminum receiver handle extended use without premature wear. 
 

Usage Notes 

The .350 Legend produces less recoil than comparable centerfire deer cartridges and qualifies for straight-wall cartridge hunting regulations in several states, which expands its usefulness beyond typical AR-platform chamberings. Ammunition availability is narrower than 5.56 or .308, which factors into long-term ownership costs.

Owners of the Ruger AR-556 MPR in .350 Legend generally describe a versatile rifle that handles both hunting and target shooting without major compromises.

The .350 Legend cartridge comes up frequently in a positive context. Users highlight its manageable recoil and effective performance on deer-sized game at moderate distances. The two-stage Ruger Elite 452 trigger gets specific praise for improving shot quality over a standard single-stage unit.

Build quality tracks with Ruger's broader reputation. The anodized finish is described as durable, and the action runs reliably across different ammunition brands.

Ammo availability and cost are the main areas of concern. Some owners note difficulty finding .350 Legend compared to more common calibers, particularly in rural or smaller markets. Aftermarket support specific to the .350 Legend platform is also more limited than for standard AR-15 chamberings, though standard AR parts work for most modifications.