AERO M5 308 STANDARD LOWER PARTS KIT

Building a custom .308 AR platform rifle starts with the right lower parts kit, and the Aero M5 308 Standard Lower Parts Kit gives you everything needed to assemble a complete lower receiver from scratch. Aero Precision's M5 line is purpose-built for .308 Winchester and similar large-frame calibers, and this kit includes all the springs, pins, levers, and selector components manufactured to mil-spec dimensions and finished to Aero's exacting standards. If you're a precision shooter, long-range hunter, or builder looking to put together a rifle on your own terms, this kit takes the guesswork out of sourcing individual parts.

The kit is engineered specifically for M5 platform lowers and includes Aero's custom-fitted takedown and pivot pins—the same pins work with DPMS-pattern lowers as well, though they'll sit slightly proud of the receiver. Every spring, detent, and pin is accounted for, meaning you won't be hunting the internet for that one part you forgot. The trigger assembly components, bolt catch mechanism, safety selector, magazine catch, and grip hardware are all here and ready to go. Whether you're building your first .308 or your fifth, having a complete kit eliminates the hassle of cross-referencing compatibility across a dozen different suppliers.

Aero's reputation in the AR-building community is built on tight tolerances and consistent quality, and this lower parts kit reflects that focus. Everything fits as intended, reduces assembly headaches, and gives you a solid foundation for whatever upper receiver and barrel setup you choose to pair with your M5 lower.

Key Features

• Complete lower parts kit for Aero M5 .308 platform builds
• Mil-spec dimensions and coating for reliable fit and durability
• Custom-fitted M5 takedown and pivot pins included
• All springs, detents, and pins accounted for—no missing components
• Trigger assembly, bolt catch, safety selector, and magazine catch hardware included
• A2 pistol grip with screw and lock washer
• Compatible with M5 pattern lower receivers; also works with DPMS-pattern lowers

Specifications

Frequently Asked Questions

Will this kit work with my DPMS lower receiver?

The M5 takedown and pivot pins will function with DPMS-pattern lowers, but they will extend slightly beyond the receiver. For a flush fit, DPMS-pattern users may prefer pins designed specifically for that pattern.

What's included in this lower parts kit?

This kit includes all the small parts needed to complete an M5 lower receiver assembly: trigger group components (hammer, trigger, disconnector, and their springs), bolt catch assembly with spring and pin, safety selector with spring and detent, takedown and pivot pins with their springs and detents, buffer retainer and spring, magazine catch body with spring and extended button, and an A2 pistol grip with mounting hardware.

Do I need anything else to finish my M5 lower receiver?

This kit supplies all the internal parts and grip hardware. You'll still need an M5 lower receiver and, for a complete rifle, an upper receiver assembly and barrel.

Is this kit suitable for hunting and long-range shooting?

Yes. The M5 platform and this kit are designed for large-frame .308 rifles, which are popular for hunting and precision long-range shooting. The mil-spec components ensure reliable function in field and range conditions.