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Questions & Answers
What weight buffer is recommended for this upper? Manufacturer Answer

We recommend not going lighter than 7.5 oz. We also have a 11oz buffer that works great with .40SW

by STERN DEFENSE, Manufacturer, November 27, 2024

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Caliber: .40 S&W Barrel Length: 8.5 inBarrel Profile: Light Weight Barrel Twist Rate: 1-16 Threads per Inch: .578x28 Color: Black Handguard Length: 10 in

Code: 3JS-URC-SD6-015SD10INMD5ML8-5INBR40SWKK

MPN: 015-SD10INCHMOD5MLOK8.5INCHBARREL40SW-KK

UPC: 850001176743

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List: $555.12Save $20.12
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Product Info for Stern Defense SD 8.5in MOD5 MLOK .40SW Upper Receiver Assembly

Handguard. The free float MLOK handguard from Stern Defense offers excellent ergonomics while remaining lightweight and strong. This handguard is MLOK compatible to accept your favorite attachments. Features a secure clamp on mounting system that ensures that the handguard remains in place even under heavy abuse, sustained full auto fire, and shooting prone from a bi-pod. Machined from 6061 aircraft grade aluminum and hard-coat anodized for longevity and durability.image

Barrel. Stern .40S&W barrels are ideal for gun lovers who want to build their own custom dedicated .40S&W AR15 upper group. Machined to tight tolerances with quality as a top priority, you can't go wrong with the SD .40 cal barrel.

Receiver. Mil-Spec flat top upper receiver with Stern Defense laser engraved dust cover and forward assist. Machined from 7075-t6 aluminum and hard-coat anodized. Mil-spec dry film lube in the bore.

Charging Handle. Mil-spec charge handle for AR-15 rifles. Laser engraved with Stern Defense logo. Their latch is Ergonomically designed and provides a positive grip and easy one hand manipulations while charging your weapon under stressful situations. Made from 6061 aircraft grade aluminum billet and hardcoat anodized.

Bolt. Made with 8620 AISI steel and boasting a Mag-Phosphate finish, the Stern bolt fits into Mil-Spec and Glock-pattern upper receivers. It functions with Colt SMG, Glock magazines and it's fully compatible with standard AR15/M16 charging handles. Comes fully assembled with all sub-components installed, including firing pin/spring/retaining pin, extractor, and extractor spring. Also included in bolt assembly is a propriety center and roll pins. Their 40SW bolts incorporate their new bolt design which caters to single stage triggers with short resets. It also allows use with the JP silent capture spring but is not recommend for 40SW applications. This bolt is compatible with the Law Tactical folding stock and the Echo trigger.

BLAST CAN. Designed to direct muzzle blast away from shooters. Which is especially helpful on short barreled rifles and pistols. Machined from 6061 aircraft grade aluminum billet and hardcoat anodized. 3.25 inches long and 1.2 inches in diameter.

Specifications for Stern Defense SD 8.5in MOD5 MLOK .40SW Upper Receiver Assembly:

Manufacturer: Stern Defense
Caliber: .40 S&W
Barrel Length: 8.5 in
Barrel Profile: Light Weight
Barrel Twist Rate: 1-16
Threads per Inch: .578x28
Color: Black
Fabric/Material: 6061 Aircraft Grade Aluminum
Handguard Length: 10 in
Gun Rail: M-LOK
Gun Make: AR Platform
Gun Model: AR-15
Weight: 15.5 oz
Bolt Carrier Group Included: MIL-SPEC
Magazine Included: No
Mount Type: M-LOK

Package Contents:

  • Stern Defense SD 8.5in MOD5 MLOK .40SW Upper Receiver Assembly
  • Stern Defense 10 inch MLOK rail(Barrel nut bolts etc.)
  • Stern Defense 8.5 inch 40SW barrel.
  • SD RBC45 BLAST CAN.
  • Stern Defense assembled upper receiver with dust cover and forward assist.
  • Stern Defense SD BU40 Glock cut bolt.
  • SD CH1 enhanced charging handle.

Stern Defense SD 8.5in MOD5 MLOK .40SW Upper Receiver Assembly Orderable Models

List of Orderable Models

  • Stern Defense SD 8.5in MOD5 .40SW Upper Receiver Assembly, 10in M-LOK Handguard, .578-28 TPI, 1-16 Twist Rate, Black, 015SD10INMD5ML8.5INBR40SWKK , MPN: 015-SD10INCHMOD5MLOK8.5INCHBARREL40SW-KK , UPC: 850001176743 , Code: 3JS-URC-SD6-015SD10INMD5ML8-5INBR40SWKK
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