YHM A3 UPPER RECEIVER ASSY BLK

Description

Yankee Hill Machine’s A3 Upper Receiver Assembly is a straightforward, no-compromise starting point for an AR-15 build or a direct upgrade to an existing lower. It suits builders who want a domestically manufactured forged receiver with the internals already installed, skipping the detail work of sourcing and fitting individual components.

The receiver is forged from 7075-T6 aluminum—the same alloy series used in aerospace and structural applications—which gives the material a meaningfully higher strength-to-weight ratio than the 6061 alloy sometimes found in lower-cost options. Machining is done entirely in-house at YHM’s Massachusetts facility, so the tolerances between the forging and the finished receiver remain under one manufacturer’s control from start to finish. The hard-coat anodize finish bonds into the surface of the aluminum rather than sitting on top of it, providing abrasion resistance that holds up through regular handling and field use without adding appreciable thickness.

The flat-top configuration leaves the full Picatinny rail free for whatever optic or iron sight setup the shooter prefers, and the “T” markings at each rail slot make returning an optic to a repeatable position straightforward. M4-style feed ramps are cut into both the barrel extension seat and the receiver itself, which helps ensure reliable feeding across a wider range of ammunition profiles and magazine types compared to earlier AR feed ramp geometry. The assembly ships complete with dust cover and forward assist already installed, ready to mate with any mil-spec lower receiver.