AR15 LOWER PARTS

The GorillaMachining.com AR15 LOWER PARTS collection delivers all the essential components required to complete or upgrade your AR-15 lower receiver build with quality, compatibility, and affordability in mind. Whether you are building a rifle from the ground up or refreshing a well-used favorite, Gorilla Machining's AR-15 lower parts kits and components offer a streamlined experience, ensuring reliable performance and easy assembly for shooters of every skill level.

Product Overview

Gorilla Machining AR15 lower parts kits are mil-spec compliant, ensuring cross-compatibility with all standard AR-15 stripped lowers (both forged and billet, from leading manufacturers). Each kit is meticulously sourced or machined from rugged alloys and polymers, with heat-treating and precise tolerances that meet or exceed military standards. The kits are curated to give you everything you need—minus the buffer tube, buffer assembly, and stock—to finish your AR-15 lower receiver and support any upper configuration you prefer.

Core Components & Inclusions

A typical Gorilla Machining AR15 Lower Parts Kit includes:

• Trigger Group: Trigger, hammer, disconnector, springs, and pins—mil-spec, single-stage design provides a crisp, reliable pull. Upgraded kits may include enhanced triggers for lighter pull weight or improved reset.

• Safety Selector Group: Selector lever, detent, and spring—standard 90-degree design for most builds.

• Magazine Catch Assembly: Mag catch, button, and spring—machined to tight tolerance for positive retention and fast reloads.

• Bolt Catch Assembly: Bolt catch lever, roll pin, plunger, and spring—hard-wearing steel to withstand repeated cycling.

• Pivot and Takedown Pins: Both with detents and springs, sized for precise installation and reliable function.

• Trigger Guard Assembly: Either basic aluminum or polymer (some kits skip for custom build flexibility), with roll pin.

• Pistol Grip: Classic A2 grip with mounting screw and washer; upgraded kits may include ergonomically enhanced grips.

• Small Parts: Buffer retainer and spring, trigger and hammer pins, disconnector spring, grip screw, etc.—all vital for flawless function and safety.

Key Features and Benefits

• Compatibility: Designed for maximum fitment with mil-spec AR-15 receivers, including popular brands like Aero Precision, Anderson, Palmetto State Armory, and other market leaders.

• Ease of Assembly: Clear kit organization and standard-sized parts minimize confusion and ensure straightforward installation by builders of all experience levels.

• Durability: Components are made from hardened steel or military-grade polymer—springs are properly tensioned for long-term, positive engagement and reliable resets.

• Customizability: Choose between basic, enhanced trigger, or minus-FCG (fire control group) kits if installing your upgrade trigger, letting you tailor the receiver for hunting, competition, or tactical uses.

• Finish Matching: Black oxide/phosphate finish matches most receivers for a unified look and improved corrosion resistance.

Technical Specifications

Performance Insights

• Assembly Experience: Reviews and users consistently note that Gorilla Machining LPKs are easy to install, drop seamlessly into mil-spec receivers, and rarely require extra fitting.

• Trigger Quality: While mil-spec triggers are a standard option for cost conscious or duty builds, Gorilla Machining kits can be paired with drop-in or match triggers for speed and precision.

• Positive Function: Steel catch levers and pins mean long-term reliability and fewer malfunctions even in high-volume shooting or field use.

Best Building Applications

• First-Time Builds: Reliable, mil-spec construction means fewer surprises, making these kits a top pick for new AR-15 owners and home assemblers.

• Upgrades/Refresh: Restore old rifles to new functionality with complete, original-spec groups.

• Custom Project Flexibility: Use "minus FCG" or "minus grip" kits for match or duty-style setups with custom triggers and grips.

• Spares/Field Repairs: Affordable pricing lets you keep a backup LPK for field or range fixes.

Assembly Tips and Best Practices

• Use proper roll pin punches and a bench block to avoid marking lower receiver finish.

• Light lube (CLP or grease) on pins and contact points aids smooth break-in and long-term reliability.

• Double-check spring orientation, especially on the safety detent and bolt catch for correct operation.

• For billet or non-mil-spec lowers, dry-fit prior to assembly to confirm tolerance stack.

Frequently Asked Questions

Q: Will Gorilla Machining AR15 lower parts fit my lower?
A: Yes, if your lower is mil-spec dimensioned (the vast majority of AR-15 forged and billet lowers sold in America).

Q: Is this kit compatible with .300 BLK, 6.5 Grendel, or 9mm ARs?
A: Yes—the lower parts are universal for AR-15 calibers. Select caliber-specific upper, mag, and buffer parts as needed.

Q: Can I use my own trigger with this kit?
A: Absolutely. Choose a kit minus FCG (fire control group), or simply swap your preferred trigger after installation.

Q: What about the stock and buffer assembly?
A: Buffer tubes, springs, stocks, and castle nuts are sold separately, allowing you to customize your setup.

Conclusion

The GorillaMachining.com AR15 LOWER PARTS kit represents the best value and performance for AR-15 builders. With robust, mil-spec-sized components, reliable spring and detent selection, and drop-in compatibility across the vast majority of AR-15 platforms, these kits are perfect for completing new builds, upgrading old rifles, or keeping spares ready for field repairs. No AR-15 project is complete without a high-quality lower parts group—and Gorilla Machining delivers consistent performance at an affordable price.