Stern Defense AR-15 SD 4 MOD4 Complete Upper Receiver 45ACP 4" M-LOK

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by Stern Defense

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Stern Defense AR-15 SD 4 MOD4 Complete Upper Receiver 45ACP 4" M-LOK

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Retail: $514.14

Overview

Stern Defense SD 4in MOD4 MLOK .45ACP upper receiver assembly for an AR-15 platform.

Handguard

  • Free-float M-LOK handguard
  • Secure clamp-on mounting system for stability under heavy use
  • Quick disconnect swivel holes
  • Machined from 6061 aircraft grade aluminum with hard-coat anodizing

Receiver

  • Mil-Spec flat top upper receiver
  • Laser engraved dust cover and forward assist
  • Machined from 7075-T6 aluminum with hard-coat anodizing
  • Enlarged ejection port for larger rounds like .45 ACP

Charging Handle

  • Mil-Spec charging handle for AR-15 rifles
  • Laser engraved with Stern Defense logo
  • Made from 6061 aircraft grade aluminum billet with hard-coat anodizing

Bolt

  • Bolt made from 8620 AISI steel with Mag-Phosphate finish
  • Fully assembled with firing pin/spring/retaining pin, extractor, and extractor spring (plus center and roll pins)
  • Designed to function with Mil-Spec and Glock-pattern upper receivers
  • Compatible with standard AR-15/M16 charging handles

Barrel / Other

  • Stern 45 ACP barrel
  • Barrel length: 4 in
  • Barrel profile: Light Weight
  • Twist rate: 1-16
  • Threading: .578x28 TPI

Color

  • Black

Specifications

Manufacturer:
Stern Defense
Category:
upper-receiver
Caliber:
.45 ACP
Platforms:
AR-15
Interfaces:
Magpul M-LOK
Weight:
15.5 oz
Length:
4.0"
UPC:
850001176613
MPN:
015SD4INCHMOD4MLOK4INCHBARREL45ACPKK
Required Component:
Yes

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Where to Buy

Optics Planet
In Stock
$498.00
MidwayUSA
Availability Unknown
$393.32

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Price History

Current

$498.00

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$473.10

Highest

$498.00

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What's Included in this Bundle

Handguard or rails
Stern Defense 4 inch M-LOK rail (barrel nut bolts etc.)
Barrel
Stern Defense 4 inch .45ACP barrel
.578x28 threads per inch (barrel thread spec provided for upper assembly).
Muzzle Device
SD MBC45 blast can
Blast can directs muzzle blast; treated as muzzle device (not a serialized suppressor).
Bolt Carrier Group
Stern Defense SD BU45 Glock cut bolt
Bolt carrier group included; page states bolt fits Mil-Spec and Glock-pattern upper receivers.
Charging Handle
SD CH1 enhanced charging handle
Bundle Price: $473.10

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