Brownells 75th Anniversary - A Shooting Heritage

Precision Reflex’s Mark 12 Mod 0 SPR Gen II Upper Receiver is a complete, full-featured tactical upper that’s fully assembled and ready to shoot...once you install it on a mil-spec lower receiver. It is fitted with PRI’s Gen II Retro Carbon Fiber Forend that replicates the handguard of the U.S. Navy’s Mk 12 Mod 0 Special Purpose Rifle. You get a mile-long, uninterrupted expanse of Picatinny top rail extending from the rear of the receiver to the front of the forend. (Maybe we exaggerate slightly - half a mile.) There are also short 3" lengths of Picatinny rail up front in the 3, 6 and 9 o’clock positions.

The Mark 12 Mod 0 SPR Gen II Upper Receiver will deliver MOA accuracy right out of the box thanks to its free-floated, 18" Douglas barrel of high-grade 416 stainless steel with 1-7" target rifling and M4-type feed ramps. The bolt is custom-fitted to the barrel. And as the late-night infomercials say, that’s not all. The SPR Gen II upper also offers:

  • PRI Gas Buster charging handle with an easy-to-grasp oversized latch
  • Precision Reflex Flip Up sights - elevation (front) & windage (rear) adjustable without tools
  • OPS muzzle brake to tame recoil & muzzle rise during rapid fire
  • 5.56x45mm NATO chamber accepts both military & civilian .223 Remington ammunition
  • Rifle-length gas system cuts gas velocity to promote excellent reliability
  • Non-reflective matte black finish on barrel, brake, receiver & forearm

The PRI Mark 12 Mod 0 SPR Gen II Upper Receiver delivers a unique combination of accuracy, performance, and versatility, but it’s pleasantly basic where it counts. The forged, mil-spec AR-15 flattop receiver comes with a standard commercial carrier, so compatibility with a mil-spec (.250" pivot/takedown) lower is no problem.


Special Order, See Associate
Special Order Item: Please allow 5-8 weeks additional processing time.

Cartridge: 5.56 mm NATO

Finish: Black

Style: Complete

Twist: 1-7