Centurion Arms MK12 Complete Upper 18"

The Centurion Arms MK12 Complete Upper is the clone-correct way to buy a turnkey MK12 SPR. Centurion builds it with the parts the issued rifle actually used, not a homage with the name stamped on it. The upper runs an 18-inch stainless match-grade, air-gauged barrel with a 1:7 twist tuned for the 77-grain match load the SPR was designed for, a low-profile MK12 gas block on a rifle-length system, and your choice of the issued PRI (Mod 0) or KAC (Mod 1) handguard. That parts list, not branding, is what makes it clone-correct.

The defining choice is the handguard, and Centurion offers both correct options: a PRI Gen III carbon-fiber forearm with the PRI SPR straight top rail for a Mod 0, or the Knight's Armament Long Free-Float RAS for a Mod 1 (Centurion also offers its own C4 quad rail). The upper ships as a configurable assembly; the Sandcutter BCG and a PRI Gas Buster or standard charging handle are add-ons.

Against the Daniel Defense MK12 URG, the Centurion is both cheaper and clone-correct: it uses the issued PRI/KAC handguards and a match barrel where Daniel Defense substitutes its own quad rail and a cold-hammer-forged barrel.