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Cross Machine Tool (CMT) Tactical UPUR - 1LH Left Hand Eject Billet Upper Receiver

Out of stock

Cross Machine Tool (CMT) Tactical UPUR - 1LH Left Hand Eject Billet Upper Receiver


The Cross Machine Tool Ultra Precision Upper Receiver Part# UPUR-1LH is the perfect Mate to your UHP-15 lower receiver or would also be a great match with any Mil-Spec lower. The UPUR-1LH is machined from Billet 7075 T6 Aluminum unlike the more commonly used 6061. Using the 7075 T6 aluminum gives the UP-UR a 65% increase in strength & rigidity over 6061 aluminum receivers. The UPUR-1LH is machined on a 5 Axis machining Center to reduce the number of operations/setups required to complete. This machining process allows the highest possible accuracy to be obtained over the traditional 3 or 4 Axis machining method. The UPUR-1LH is designed for increased function, performance & to provide an advanced modern appearance & feel to the AR15 platform weapon system. The Left Hand eject of the UPUR-1LH drastically reduces the amount of gasses exiting the chamber into the face of left handed shooters when shooting suppressed.


The UPUR-1LH is available for order only thru Rainier Arms


  • 5 axis machined from 7075 T6 billet

  • M4 feed ramps

  • Engraved “T” numbers

  • 1913 picatinny Rail flat top

  • Mil Spec Type III class II hard coat anodized Black

  • Shell deflector

  • Forward Assist machined into receiver

  • Increased wall thickness for added rigidity

  • Compatible with Mil spec parts

  • Compatible with most aftermarket handguard/rail systems

  • Lifetime warranty against manufacture defects

  • Comes stripped without forward assist assembly

  • This upper does not support the use of a dust cover

  • Compatible with Stag Arms LH BCG only or comparable

MSRP - $159.50

More Information
SKU UPUR-1LH Left Eject Upper
Manufacturer Cross Machine Tool (CMT)
Option AR-15