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Build Kits
Build Kits

Complete AR-15 Build Kits – Everything You Need in One Box

Simplify your next project with a Complete AR-15 Build Kit from Tactical Machining. We have taken the guesswork out of compatibility by pairing our premium, American-made 80% lower receivers with factory-assembled uppers and high-quality lower parts kits.

Whether you are building a standard 16" 5.56 NATO Rifle or a compact .300 Blackout Pistol, these bundles provide every single part required to finish your build—just add a jig and your tools.

What is Included?

Our build kits are curated to ensure perfect fitment between the upper and lower receiver. Instead of hunting for individual pins and springs, our kits typically include:

  • The Foundation: A Tactical Machining 80% Lower Receiver (6061 Billet or 7075 Forged).
  • The Upper: Fully assembled upper receiver with barrel, gas system, and handguard installed.
  • The Internals: Full Bolt Carrier Group (BCG) and Charging Handle.
  • The Finishing Parts: Complete Lower Parts Kit (LPK) and Buffer Tube Assembly (with stock or brace).

Why Choose a Tactical Machining Kit?

1. The 6061 Billet Advantage

Most generic build kits come with standard forged lowers that can have an inconsistent finish. Our kits feature our signature 6061-T6 Billet Lowers. This offers three distinct advantages for the home builder:

  • Easier Machining: 6061 is softer than 7075, meaning you get a cleaner cut with less chatter, extending the life of your jig and router bits.
  • Superior Finish: Our 6061 lowers take anodizing perfectly for a deep, rich black color that matches high-end uppers.
  • Corrosion Resistance: 6061 is inherently more resistant to rust and oxidation than 7075, protecting your investment for the long haul.

2. Guaranteed Compatibility

The biggest frustration in building an AR-15 is "tolerance stacking"—when parts from different companies technically fit but wobble or rattle. By buying a Tactical Machining Build Kit, you are getting an Upper and Lower receiver that were verified to work together. We check the fitment so you don't have to.

3. What Else Do I Need?

These kits contain everything strictly required for the firearm itself. To complete the 80% lower, you will need an 80% Lower Jig and the appropriate tooling (router or drill press). Once machined, the parts in this kit will install with standard tools (punches, castle nut wrench, etc.).