Fightlite Industries 15076 Main Action Spring 223 Rem/5.56 Nato Rifles

The Fightlite Industries 15076 Main Action Spring is a purpose-built replacement spring for .223 Rem/5.56 NATO rifles, engineered to restore reliable cycling in belt-fed MCR (Modular Carbine Rifle) platforms and compatible upper receiver assemblies. If you're running a Fightlite MCR or similar modern sporting rifle and experiencing sluggish bolt cycling, feeding issues, or simply maintaining your rifle through a parts refresh, this main action spring is the drop-in solution you need to keep your rifle running like it should.

Action springs are critical to reliable rifle function—they control the force that drives the bolt carrier group forward after firing, affecting everything from feeding consistency to overall cycling reliability. A weakened or worn spring can lead to short stroking, failure-to-feed, or inconsistent performance, especially in a belt-fed system where smooth operation under sustained use is essential. Fightlite's main action spring is designed to deliver the correct spring rate for .223/5.56 NATO applications in their rifles, ensuring your gun cycles as intended.

This is a genuine OEM-spec part, not an aftermarket substitute. Whether you're a competitive shooter, an operator running training courses, or a hunter relying on your rifle in the field, having the correct replacement spring on hand is basic maintenance wisdom. Spring replacement is a straightforward gunsmithing task, making this an accessible upgrade you can perform yourself with basic tools.

Key Features

• Designed for Fightlite MCR rifles and compatible .223 Rem/5.56 NATO upper receiver assemblies
• OEM-spec main action spring for reliable bolt carrier group cycling
• Direct fit—no fitting or modification required
• Restores consistent feeding and cycling performance in belt-fed platforms

Specifications

Frequently Asked Questions

What rifles is this main action spring compatible with?

This spring is designed for Fightlite MCR rifles and compatible upper receiver assemblies chambered in .223 Rem/5.56 NATO. Verify your specific platform before ordering.

Will this spring fit my standard AR-platform rifle?

This is an MCR-specific component. If you're unsure whether your rifle is compatible, contact us or consult Fightlite's documentation for your platform.

What does a main action spring do?

The main action spring drives the bolt carrier group forward after firing, controlling cycle rate and ensuring reliable feeding. A worn or incorrect spring can cause feeding failures or sluggish cycling, especially under sustained use.

Do I need special tools to install this?

Main action spring replacement is a basic gunsmithing task requiring standard tools. If you're not comfortable performing the work yourself, take your rifle to a qualified gunsmith.