Mk12 Mod 1 Near Clone Upper Receiver Group, complete from Potomac Armory

Mk12 Mod 1 Near Clone Upper Receiver Group — Complete Build from Potomac Armory | SPR Precision at an Accessible Price

The Mk12 Mod 1 SPR is one of the most sought-after clone builds in the AR community, and sourcing every contract-correct component can take months and cost well north of what most builders budget. This near-clone upper from Potomac Armory bridges the gap — it delivers Mk12 Mod 1 accuracy and aesthetics using high-quality components that match the profile and function of the military specification without requiring unobtanium-grade contract parts.

What "Near Clone" Means

A "near clone" uses components that match the form, fit, and function of the military specification but may not carry the exact contract manufacturer markings or NSN-traceable provenance. In this case, the 18" SPR-profile barrel is match-grade with the correct contour and twist rate, paired with Allen Engineering AEM5 suppressor-compatible hardware. The rail, sights, and mount options let you configure the upper to your preferred level of correctness. This is a complete upper — barrel, handguard, gas system, and muzzle device installed and headspaced, ready to drop onto your lower receiver.

Configuration Options

Potomac Armory builds these uppers with your choice of barrel profile, sight configuration, and scope mount — see the product options above for current availability. Every upper is assembled and test-fired by Potomac Armory before shipping to CCC.

Complete Your Mk12 Build

→ Nightforce NXS 2.5-10x24 — The Mk12 Mod 1 Optic

→ A.R.M.S. #22 Medium 30mm Rings for Mk12

→ A.R.M.S. #32 Harris Bipod Adapter

For SPR and Mk12 build guidance — whether you are going full clone-correct or near-clone — CCC has been assembling and advising on these platforms since 2017.