Product Code: 29009-BLK


Current Stock:

New Frontier Armory Pistol Caliber Billet AR-9/45 “Slick Side” Upper with LRBHO — PATENT PENDING

Manufactured to MILSPEC on state of the art CNC equipment for consistent quality parts and exacting tolerances Save money by building your own AR-9 rifle or pistol from the ground up exactly the way you want it configured Designed to match lines with New Frontier Armory C-9 & C-45 Billet Lower Contains integrated Last Round Bolt Hold Open (LRBHO) technology (PATENT PENDING) that reliably holds the bolt open when magazine is empty LRBHO feature is designed for lowers that accept Glock style magazines.

Once assembled the small “hook” end of the wire form in the upper should be pushed up by the follower of an empty Glock magazine which will engage the bolt catch on the last round fired to hold the bolt in the locked position. If it does not engage, or engages before the last round is fired you can make VERY SMALL adjustments by SLIGHTLY bending the “hook” end down to lock faster or up to lock slower. They are set and function checked during assembly with brand new Glock magazines and our standard bolt catches. 

Due to varying magazine specs, magazine specs changing over the life of the product, different thicknesses of the pad on the bolt catch and other variables, this adjustment may be necessary with your specific parts.

  • Caliber: Multi - Will accept any barrels, bolts and parts designed for the AR9/40/45 style platform
  • Machined from 7075-T6 Billet Aluminum
  • Hard Coat Anodized Type 3 Class 2 
  • Has integrated Last Round Bolt Hold Open function (LRBHO)
  • Is compatible with most mil-spec AR15/AR9 components
  • IS not machined for a gas tube as it's intended for gas blowback systems

NOTE: Some rail systems that use anti-rotation tabs may need slight modification to fir this upper as it's designed for flushing mounting rails and standard hand guards.