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Most Recent Reviews
As the title say this item is more fun than the law should allow, It's a dream to assemble and is a blast to fire with or without my suppressor.
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Product Discontinued by Manufacturer

Stern Defense SD 4in MOD4 MLOK .45ACP Upper Receiver Assembly has been discontinued by Stern Defense and is no longer available. Our product experts have helped us select these available replacements below.You can also explore other items in the Gun Parts, AR 15 Parts, Rifle Parts, AR15 Upper Receivers yourself to try and find the perfect replacement for you!

Product Info for Stern Defense SD 4in MOD4 MLOK .45ACP Upper Receiver Assembly

Handguard. The free float M-LOK handguard from Stern Defense offers excellent ergonomics while remaining lightweight and strong. This handguard is M-LOK 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. These handguards also feature quick disconnect swivel holes.image

Barrel. Stern 45acp barrels are ideal for gun lovers who want to build their own custom dedicated 45acp AR15 upper group.

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. This uppers ejection port has been enlarged to work with larger rounds like the 45acp and etc.

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 45 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 45 acp applications. This bolt is compatible with the law tactical folding stock.

MBC45. 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 hard coat anodized. 1.75 inches long and 1.2 inches in diameter.

Package Contents:

  • Stern Defense SD 4in MOD4 MLOK .45ACP Upper Receiver Assembly
  • Stern Defense 4 inch M-LOK rail(Barrel nut bolts etc.)
  • Stern Defense 4 inch 45acp barrel.
  • SD MBC45 blast can.
  • Stern Defense assembled upper receiver 45 with dust cover and forward assist.
  • Stern Defense SD BU45 Glock cut bolt.
  • SD CH1 enhanced charging handle.

Stern Defense SD 4in MOD4 MLOK .45ACP Upper Receiver Assembly Accessories

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Gunsmithing Tools & Accessories

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Gun Triggers

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Magazine and Accessories

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Gun Sights

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Related Products to Stern Defense SD 4in MOD4 MLOK .45ACP Upper Receiver Assembly

Stern Defense SD 4in MOD4 MLOK .45ACP Upper Receiver Assembly Unavailable & Discontinued Models

List of Unorderable Models

  • Stern Defense SD 4in MOD4 MLOK .45ACP Upper Receiver Assembly, 4in M-LOK Handguard, .578-28 TPI, 1-16 Twist Rate, Black, 015SD4INMD4ML4INBR45ACPKK , MPN: 015-SD4INCHMOD4MLOK4INCHBARREL45ACP-KK , UPC: 850001176613 , Code: 3JS-URC-SD9-015SD4INMD4ML4INBR45ACPKK
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