The AR-15 Left Hand 10.5" .300 Blackout Slim M-LOK Upper is designed for left-handed shooters who want to build a versatile, compact, and high-performance .300 AAC Blackout rifle. This upper assembly includes everything needed for a reliable and durable AR-15 build with a 10.5" Mid-Government Profile Barrel, Nitride Finish, and M-LOK handguard for modular accessory attachment. Ideal for both tactical and recreational shooting, this setup is chambered in .300 Blackout, providing versatility with both subsonic and supersonic ammunition.
The left-hand A3 flat top upper receiver comes with forward assist and ejection port cover, offering durability and functionality. This assembly also features a pistol-length gas system with a .750" low profile micro gas block, ensuring smooth cycling. Whether you're building a short-barrel rifle (SBR) or just want to customize your rifle, this upper has the features you need for a top-tier shooting experience.
Barrel: 10.5" .300 Blackout 4150 CMV steel with 1:7 twist for optimal stabilization, hardened to 26-32 RC for added strength.
Muzzle Device: 5/8x24 threads with a black A2 flash hider for muzzle control.
Upper Receiver: Left-hand A3 flat top made from 7075-T6 aluminum, black hard coat anodized, with forward assist and ejection port cover installed.
Gas System: Pistol-length gas tube with low profile .750 micro gas block made from 4140 steel for durability.
Handguard: 10" Slim Design M-LOK handguard made from 6061-T6 aluminum, black anodized for durability and a sleek profile.
Compatibility: Fits standard AR-15 lowers and is perfect for left-handed shooters.
Barrel Length: 10.5"
Barrel Profile: Mid-Govt Profile
Barrel Material: 4150 CMV steel
Twist Rate: 1:7
Chamber: .300 AAC Blackout
Barrel Finish: Nitride
Muzzle Thread: 5/8x24 with A2 flash hider
Upper Receiver: Left-hand A3 flat top (7075-T6 Aluminum, Hardcoat Anodized)
Gas System: Pistol-length gas tube with .750" low profile micro gas block (4140 steel)
Handguard: 10" Slim M-LOK (6061-T6 Aluminum, Hardcoat Anodized)
Feed Ramp: M4 Feedramps
Ejection Port: Left-hand ejection
Weight: Approx. 2.5 lbs (without BCG and CH)
Does Not Include BCG or Charging Handle
Images may not be an exact representation of the product. Mlok design variations may occur based on stock availability
Tags: ar-15, 300, aac, blackout, 10.5 10.5 left, hand, 10.5 10.5", .300, slim, m-lok, upper, 4150, cmv, 1:7, twist