Ruger AR-556 MPR 18 Semi-Automatic Rifle .223 Rem

Ruger AR-556 MPR 18 .223 Rem

The 18-inch MPR is built for mid-range precision, pairing an 18″ cold hammer-forged barrel with a rifle-length gas system for the smoothest cycling in the MPR lineup. It retains the MPR’s premium features: a 15″ M-LOK free-float handguard, the Ruger Elite 452 two-stage AR-Trigger with a crisp 4.5 lb pull, and forged 7075-T6 receivers that are Type III hard-coat anodized. The longer barrel and rifle-length gas port yield better velocity, lower port pressure, and improved accuracy on heavier bullets (up to 77 gr) — a strong choice for the shooter who wants one AR that handles both defensive and precision work.

Rifle-Length Gas System

The rifle-length gas system is the longest common AR-15 gas system. The longer dwell time means lower port pressure, which translates to less violent bolt cycling, less wear, and a softer-shooting rifle. It is the most refined setup for an 18″-class barrel.

18″ Cold Hammer-Forged Free-Float Barrel

An 18″ barrel extracts more velocity from the .223 / 5.56 than a typical 16″, especially with 69–77 gr match bullets. Free-floating the barrel keeps the handguard from influencing barrel harmonics, and the 5-groove cold hammer forged bore delivers outstanding accuracy straight from the factory.

Ruger Elite 452 Two-Stage Trigger

The same two-stage trigger as the 16″ MPR — ~4.5 lb, crisp, predictable — is an ideal match for precision work at longer distances.

15″ M-LOK Free-Float Handguard

The extra 1.5″ of handguard vs. the 16″ MPR gives more real estate for hand positioning, bipod attachment, and accessory mounting while still floating the barrel cleanly.

Premium Components Included

• Ruger Elite 452 two-stage AR-Trigger, ~4.5 lb
• 15″ M-LOK free-float handguard
• Rifle-length gas system
• Forged 7075-T6 receivers, M4 feed ramps, Type III hard-coat anodized

Specifications