Midwest Industries MILRB AR-15 Lower Receiver Block Blue Polymer

The Midwest Industries MILRB Lower Receiver Block transforms AR-15 maintenance and assembly work from a frustrating struggle into precise, controlled operation. This blue polymer block secures mil-spec lower receivers in bench vises, eliminating movement and potential damage during trigger group installation, buffer tube threading, and general maintenance tasks.

What Makes This Different

Unlike generic receiver blocks that rely on loose magazine well fits, the MILRB features precision-molded dimensions that match mil-spec lower receiver tolerances exactly. The durable polymer construction distributes clamping pressure evenly across the receiver's magazine well, preventing stress concentrations that can crack aluminum receivers. This block accommodates both forged and billet lower receivers without modification.

Key Features

• Precision-molded blue polymer construction fits mil-spec AR-15 lower receivers
• Designed specifically for magazine well clamping without receiver damage
• Compatible with standard bench vises and armorer's blocks
• Eliminates receiver movement during trigger installation and maintenance
• Lightweight polymer won't mar or scratch receiver finishes
• Accommodates both forged and billet lower receiver profiles
• Integrated features prevent over-tightening and stress concentration

Professional armorers and serious enthusiasts rely on proper fixturing for consistent, damage-free work. The MILRB block maintains receiver alignment during buffer tube installation, preventing cross-threading that can ruin expensive receivers. The polymer material provides sufficient grip without the hardness that causes finish damage or stress cracking common with metal blocks.

Technical Specs

• Material: High-strength blue polymer construction
• Compatibility: Mil-spec AR-15 lower receivers (forged and billet)
• Mounting: Standard bench vise compatible
• Color: Blue polymer finish
• Weight: Lightweight polymer construction
• Manufacturer: Midwest Industries
• Country of Origin: United States

The MILRB represents essential tooling for anyone performing regular AR-15 maintenance or builds. Quality receiver blocks prevent costly mistakes and ensure professional results every time.