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Drontheim – Complete Upper, no Forward Assist, 10.5″ 300BLK 1:7 Barrel, 10″ M-LOK Handguard

$598.99

Drontheim Build Works

This complete upper features a smooth-side receiver without forward-assist, true to the original design by Eugene Stoner, combined with a Ballistic Advantage 10 inch, 1:7 twist, 5R button rifled, QPQ-lined barrel, and 10 inch octagonal free-float M-LOK handguard.

In stock

SKU: DBW-SSR-300-105N-108-010-1 Category: Tag:

Description

This complete upper features a smooth-side receiver without forward-assist, true to the original design by Eugene Stoner, combined with a Balistic Advantage 10 inch, 1:7 twist, 5R button-rifled, QPQ-lined Chrome Molybdenum Vanadium barrel, and 10 inch octagonal free-float M-LOK handguard.

Includes

Smooth-side upper receiver

Ideal for lightweight builds, this milspec-compatible upper weighs 4 oz. less than the same upper with Forward Assist.

Forged from 7075-T6 aluminum, this assembled upper is precision machined to mil-spec M16/M4 specifications and features M4 feedramps.  The no-forward assist upper receivers use a custom forging designed to work specifically with mil-spec port doors. It may not work with aftermarket port doors.

Features:

• M4 feed ramps
• 0.250 takedown holes
• laser engraved t-marks
• installed port door

Ballistic Advantage 10″, Modern Series barrel

Each Faxon barrel goes through a battery of tests at each operation until finished and final inspected.  All barrels are individually checked for headspace by precision custom hardened gauges.  This includes MPI inspection of every single barrel.  Bore concentricity is also checked, and confirmed to be within .0002” of perfectly true.

This barrel has a pistol-length gas system, with a 0.750″ low-profile gas block for optimal reliability with both subsonic and supersonic ammunition.

The 5R rifling used has 5 lands and grooves which puts lands opposite of grooves.  Further, the transition from the top of the land to the groove is sloped.  This reduces projectile deformation as it passes through the bore during the firing sequence.  By placing the lands opposite of the grooves, the bullets are no longer squeezed on opposite sides ensuring the projectile stays uniform instead of squeezing material into the grooves.  More uniform projectile means better accuracy.  By sloping the transition to the groove, the barrels become much easier to clean. In a conventionally rifled platform, these corners become depositories for lead and superheated materials left after shooting.  Cleaning supplies have a hard time reaching these corners as they are incredibly small.  By sloping it, cleaning supplies are easily able to get to the deposits.

Additionally, this barrel is QPQ-lined for it’s high corrosion resistance, improved lubricity, for ease of cleaning, and increased barrel life.

Features:

• 1:7 twist
• dual-radius profile
• 416-R stainless
• 5R button rifling
• pistol length gas system
• 0.750″ low-profile gas block
• M4 barrel extension
• QPQ Nitride finish
• NP3 lining
• 5/8×24 muzzle threading
• A2 Flash Hider (unpinned)

10″ Octagonal free-float M-LOK handguard

These lightweight and solid M-LOK free float handguards for your AR-15 are built to provide rugged, reliable performance, and have been designed with advanced shooter in mind. As a result, they are sleek and ergonomic in the hand, which translates into faster on target performance and ease of use.

Additionally, the picatinny rail is dovetail-bevelled for ease in precision-mounting attachments, and grooved and slotted for optimal airflow and cooling.

Most other M-LOK handguards offer only three rows of M-LOK rail, and the remaining four angles merely provide ventilation. In addition to the top picatinny rail, this handguard provides full M-LOK compatibility on all SEVEN other sides.

Features:

• 6061-T6 Aluminum
• Black Hardcoat Anodized
• 1.35″ inner diameter
• full-length picatinny rail
• anti-rotation tabs
• 7-sided MLOK, for superior flexible mounting options

Note: This complete upper does not include a BCG or Charging Handle. These products may be selected as add-ons below.


To finish your build

Weight32.375 oz
Dimensions21.125 × 4.125 × 4.125 in

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