Colt M4 FBP Configuration Carbine Rifle 5.56mm 30rd Magazine 16.1″ Barrel Matte Black Collapsible Stock

Description

The Colt M4 FBP Configuration Carbine Rifle 5.56mm 30rd Magazine 16.1″ Barrel Matte Black Collapsible Stock is a factory-assembled carbine that takes the proven LE6920 platform and outfits it with a Geissele MK4 13-inch M-LOK rail system and Magpul Pro flip-up sights. This is not a parts-bin build; it is a Colt factory configuration with a chrome-lined 4150 CMV barrel, 1:7 twist, and a reversible safety selector. The result is a duty-ready rifle that retains Colt’s mil-spec pedigree while upgrading the handguard and sighting system for modern handling.

Manufacturer	Colt Defense
Model	LE6920-FBP
Material	7075-T6 aluminum upper and lower receivers; 4150 chrome moly vanadium barrel
Compatibility	Standard AR-15 lower parts, magazines, and accessories
Finish	Matte black hardcoat anodized
Weight	7.3 lbs. unloaded (per Colt specs)
Condition	New factory configuration

Key Features

• Geissele MK4 13-inch M-LOK rail system — Why it matters: The continuous top rail and M-LOK slots give you a rigid mounting surface for lights, lasers, and grips without adding bulk. Geissele rails are known for their tight fit and consistent torque.
• Magpul Pro flip-up front and rear sights — Why it matters: These are low-profile, all-metal backup sights that co-witness with most red dots. They deploy instantly and lock up solid, no windage creep.
• Chrome-lined 4150 CMV barrel with 1:7 twist — Why it matters: Chrome lining extends barrel life and eases cleaning, while the 1:7 twist stabilizes heavier bullets (62-77 grain) commonly used for duty and match loads.
• Reversible safety selector — Why it matters: Ambidextrous operation out of the box accommodates left-handed shooters or off-hand manipulations without aftermarket parts.
• Collapsible carbine stock with six-position adjustment — Why it matters: Allows length-of-pull adjustment for body armor, heavy clothing, or different shooter builds, keeping the rifle balanced.

Who It’s For

This carbine is built for shooters who want a factory-assembled rifle with upgrades already installed — no need to buy a rail and sights separately or trust a local gunsmith. It suits patrol officers, 3-gun competitors, and serious home-defense users who demand reliability and a consistent shooting experience. If you appreciate Colt’s mil-spec heritage but want a more modern handguard, this configuration bridges that gap.

Pros & Cons

• Pros: Factory Colt assembly; Geissele rail is top-tier; Magpul Pro sights hold zero; chrome-lined barrel for longevity; reversible safety for lefties.
• Cons: The Geissele rail adds weight over a standard M4 handguard; the Magpul Pro sights, while robust, are not as fast to acquire as a red dot for close-range work. This rifle also lacks a free-float barrel nut from the factory — though the Geissele rail includes its own barrel nut, the barrel is not free-floated in the traditional sense.

Comparison

Feature	Colt LE6920-FBP	Zev Technologies OZ9C	Geissele Super Duty 16-inch
Caliber	5.56mm	9mm	5.56mm
Barrel length	16.1″	4.5″	16″
Rail system	Geissele MK4 13″	Zev Z9 grip module	Geissele MK16 13.5″
Weight (unloaded)	7.3 lbs.	1.8 lbs.	6.9 lbs.
MSRP	$1,652.53	$1,299.00	$1,999.00

Compared to the Zev OZ9C, the Colt is a full-size rifle chambered in 5.56mm — the Zev is a compact pistol-caliber carbine. Against the Geissele Super Duty, the Colt offers a similar rail and barrel quality at a lower price point, though the Super Duty includes a free-floated barrel and a different gas system.

FAQ

Is the barrel chrome-lined?

Yes, per Colt specs the 16.1-inch barrel is chrome-lined on the bore and chamber. This improves corrosion resistance and extends service life, especially under sustained fire.

Does this rifle come with a carry handle?

No, the LE6920-FBP ships with Magpul Pro flip-up front and rear sights only — no carry handle is included. The flat-top upper receiver allows direct mounting of optics.

Can I use standard AR-15 magazines?

Yes, it accepts all standard AR-15/M16-pattern magazines in 5.56mm or .223 Remington. The included magazine is a 30-round Colt-branded unit.

Is the Geissele rail compatible with other uppers?

The MK4 rail uses a proprietary barrel nut designed for mil-spec upper receivers. It will fit any standard AR-15 upper with a .750-inch gas journal, provided the barrel nut is installed correctly.

Secure Checkout & Delivery

• ✔ Nationwide delivery (all 50 states)
• ✔ Ships 1-2 business days
• ✔ 30-day returns
• ✔ Secure checkout

Last updated: April 2026

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