Davidson Defense Undertow 16-inch Carbine-Gas 1:7 5.56 NATO AR-15 Freefloat M-Lok Handguard Rifle Full Build Kit

Undertow 16 Inch Carbine Gas 1:7 5.56 NATO AR 15 Freefloat M Lok Handguard Rifle Full Build Kit

The Undertow 16 inch full build kit delivers a 5.56 NATO setup built around a 16 inch cold hammer forged M4 profile barrel with 1:7 twist and carbine length gas system. The 15 inch freefloat M Lok handguard with full length Picatinny top rail provides modular mounting surfaces while maintaining a lightweight profile. This kit includes the upper assembly, bolt carrier group, charging handle, buffer system, lower parts kit, and adjustable carbine stock.

Key Features

• 16 inch M4 profile barrel, cold hammer forged, 4150 CrMoV steel, phosphate finish, 1:7 twist rate, 5.56 NATO chambered
• AR-15 upper receiver with M4 feed ramps, 7075 T6 aluminum, anodized finish
• 15 inch freefloat M Lok handguard with full length Picatinny top rail, integrated QD sling mounts
• Micro low profile gas block, 0.75 diameter, steel construction
• Carbine length gas tube optimized for 16 inch barrel
• AR 15 bolt carrier group, 9310 alloy steel, nitride finish
• Mil spec charging handle
• Heavy duty 6 position buffer tube, 3 oz buffer weight
• Lower parts kit included
• Adjustable carbine stock, nylon reinforced polymer, black
• A2 birdcage flash hider, 1/2x28 thread pitch
• 5.56 NATO caliber, AR-15 platform

Perfect For

• AR-15 builders seeking complete rifle build with cold hammer forged barrel
• Shooters wanting reliable 5.56 NATO platform
• All purpose applications from range to defensive use
• Builders preferring M4 profile barrel with premium construction

Cold Hammer Forged M4 Profile Barrel

The 16 inch barrel features cold hammer forged construction from 4150 CrMoV steel. Cold hammer forging compresses the steel during manufacturing, creating a denser grain structure that enhances strength and accuracy potential. The M4 profile provides appropriate rigidity while balancing weight. Phosphate finish provides corrosion resistance and durability. The 1:7 twist rate stabilizes a wide range of projectile weights from 55 to 77 grains effectively. Carbine length gas system provides reliable cycling across varied ammunition types.

Freefloat M Lok Handguard with Picatinny Top Rail

The 15 inch freefloat M Lok handguard extends nearly to the muzzle device, maximizing usable mounting length. Full length Picatinny top rail allows traditional optics and accessory mounting while M Lok slots on sides and bottom provide modular attachment. Integrated QD sling mounts allow quick detach sling attachment without additional hardware. The freefloat design eliminates contact with the barrel for improved accuracy potential.

M4 Feed Ramps for Reliable Feeding

The upper receiver features M4 feed ramps machined into the receiver extension. These extended feed ramps guide cartridges smoothly from the magazine into the chamber, reducing feeding issues with varied ammunition types. M4 feed ramps are standard on modern AR-15 platforms and ensure compatibility with most barrels and bolts.

Premium Bolt Carrier Group

The bolt carrier group features 9310 alloy steel construction with nitride finish. This material provides enhanced wear resistance and corrosion protection in a high pressure platform. The nitride treatment penetrates the steel surface rather than coating it, maintaining dimensional tolerances while adding durability.

Adjustable Carbine Stock

The adjustable carbine stock features nylon reinforced polymer construction in black. Six position adjustability allows length of pull customization for different shooting positions, clothing, or body armor. The adjustable design accommodates multiple users or changing conditions.

Full Build Kit Components

This kit includes the upper assembly with barrel and handguard, bolt carrier group, charging handle, buffer tube, buffer, recoil spring, castle nut, end plate, lower parts kit, and adjustable carbine stock. Lower receiver not included. The cold hammer forged barrel and premium components provide a solid foundation for a reliable AR-15 build.

Follow safe handling and manufacturer instructions. Lower receiver not included. Ensure compliance with all applicable laws.