CMMG 55CA601 AR15 GUN BUILDERS LOWER PARTS KIT

The CMMG 55CA601 Gun Builders kit is an AR-15 lower parts kit designed for builders who plan to add their own trigger, grip, and other upgraded components. It provides the core small parts needed to complete a mil-spec AR-15 lower while letting you choose your preferred fire control group and furniture.

Key Features

• Model: CMMG 55CA601 Gun Builders kit
• Platform: AR-15 lower receiver
• Parts included: Bolt catch, bolt catch plunger, bolt catch spring, bolt catch roll pin
• Parts included: Trigger and hammer retaining pins
• Parts included: Safety selector, safety detent, safety detent spring
• Parts included: Magazine catch, magazine catch spring, magazine release button
• Parts included: Pivot pin, takedown pin, pivot pin detent and spring, takedown pin detent and spring
• Parts included: Buffer retainer and buffer retainer spring
• Compatibility: Fits most mil-spec AR-15 lower receivers

Special Features

• Omits commonly upgraded parts such as the trigger group, pistol grip, and often the trigger guard so builders can choose premium components.
• All parts are made to meet or exceed mil-spec dimensions for reliable fit and function in AR-15 lowers.
• Organized as a dedicated Gun Builders kit to simplify sourcing small parts for custom builds.
• Ideal for replacing worn lower small parts or completing stripped lowers kept on hand for future projects.
• Backed by CMMG’s reputation for quality AR-15 components and build parts.

Practical Benefits

• Lets AR-15 builders pair the CMMG Gun Builders kit with their choice of aftermarket trigger, grip, and stock for a fully customized rifle.
• Saves time and hassle by providing all the critical pins, springs, and controls needed to get a lower operational.
• Useful for home builders, armorers, and shops that regularly assemble or service AR-15 platforms.
• A solid fit for budget conscious builds where reliability and mil-spec compatibility still matter.
• Practical choice for keeping a spare small parts kit on hand to quickly repair or complete an AR-15 lower.

The CMMG 55CA601 Gun Builders kit is a practical choice for AR-15 builders who want a reliable lower parts kit while still selecting their own trigger, grip, and other upgraded components.