Broken Arms 80% Lower Jig – AR15/AR9 (With Tooling) | Polymer80

About this product

Broken Arms 80% Lower Jig: Precision Tooling for AR15 and AR9 Builds

A tier-one 80% jig designed for completing multiple lowers with unmatched accuracy.

The Broken Arms Jig is engineered for at-home fabrication, offering easy-to-follow templates and guides for milling and drilling any forged or billet lower receiver blank. Compatible with both AR9 and AR-15 80% lowers, this jig includes high-speed steel bits that can handle multiple builds before needing replacement, ensuring durability and cost-effectiveness.

What’s Included in the Kit

• (2) Side plates with drill bushings for precise alignment
• (5) Template plates for various fabrication steps
• (4) ¼-20 x ¾” jig fasteners and (2) ¼-20 x 2 jig fasteners for secure mounting
• (1) Detailed instruction manual with step-by-step guidance
• (1) Set of drill bits and (1) Set of end mill bits for complete machining

Technical Specifications and Compatibility

• Compatible with AR15 and AR9 80% lower receivers
• Materials: High-strength steel and durable components
• Designed for use with drill presses and standard machining tools
• Ideal for multiple uses, reducing the need for frequent replacements

Additional Tools Required

• Drill Press for accurate drilling operations
• Drilling Vise to secure the lower during fabrication
• Machining Oil to lubricate and extend tool life
• Eye Protection and Ear Protection for safety during use

For all your gunsmithing needs, explore our shop to find compatible tools and accessories.

Backed by Polymer80‘s reputation for quality and innovation, this jig is a must-have for DIY firearm enthusiasts looking to build reliable AR-platform rifles at home. Always follow local laws and safety guidelines.