CMMG

Lower Parts Kit - AR15

  • Lower Parts Kit - AR15

CMMG

Lower Parts Kit - AR15

AR‑15 Lower Parts Kit (LPK)

Everything you need to assemble your AR‑15 lower receiver, packaged in convenient color‑coded packets to simplify installation. Pair this kit with a buttstock or brace kit to complete your lower group.

Overview

This lower parts kit contains all common small parts and springs needed to build a functional AR‑15 lower. Ideal for first‑time builders and experienced hobbyists alike — the color‑coded packaging speeds parts identification during assembly and helps prevent lost springs and pins.

Includes

  • Bolt catch assembly

    • Bolt catch & roll pin

    • Bolt catch plunger & spring

  • Trigger group

    • Trigger

    • Trigger spring

    • Disconnector

    • Disconnector spring

    • Hammer

    • Hammer spring

    • Trigger/hammer retaining pins

  • Safety & controls

    • Safety selector (ambidextrous options vary by SKU)

    • Safety detent & spring

    • Magazine catch, spring & release button

  • Pins & detents

    • Pivot & takedown pins

    • Pivot/takedown detents & springs

  • Grip & buffer

    • A2‑style pistol grip, grip screw & washer

    • Buffer retainer & spring

  • Misc

    • Trigger guard & roll pin

Installation Resources

  • Watch our interactive install walkthrough video (linkable on product page) for step‑by‑step guidance.

  • Read the LPK Install resource article for a detailed breakdown and torque/fit tips.

Notes & Compatibility

  • Designed for standard AR‑15 lower receivers.

  • Some lower receivers or aftermarket parts (non‑standard tolerances) may require light fitting.

  • Does not include lower receiver, buttstock/brace, buffer tube, buffer, or extension — sold separately.